How do minerals differ in their properties. Therapeutic properties of mineral water for adults and children

The definition of minerals is carried out by physical properties, which are determined by the material composition and structure. crystal lattice mineral. These are the color of the mineral and its powder, brilliance, transparency, the nature of fracture and cleavage, hardness, specific gravity, magnetism, electrical conductivity, malleability, brittleness, flammability and smell, taste, roughness, fat content, hygroscopicity. When determining some minerals, their ratio to 5-10% hydrochloric acid can be used (carbonates boil).

The question of the nature of the coloration of minerals is very complicated. The nature of the colors of some minerals has not yet been determined. At best, the color of a mineral is determined by the spectral composition of the light radiation reflected by the mineral or is determined by its internal properties, by some chemical element that is part of the mineral, by finely scattered inclusions of other minerals, organic matter and other reasons. The coloring pigment is sometimes distributed unevenly, in stripes, giving multi-colored patterns (for example, in agates).

Irregular bands of agate

The color of some transparent minerals changes due to the reflection of light incident on them from internal surfaces, cracks or inclusions. These are the phenomena of the iridescent color of the minerals chalcopyrite, pyrite and iridescence - blue, blue overflows of labrador.

Some minerals are multicolored (polychrome) and have different colors along the length of the crystal (tourmaline, amethyst, beryl, gypsum, fluorite, etc.).

The color of the mineral can sometimes be diagnostic. For instance, water salts copper have green or blue color. The nature of the color of minerals is determined visually, usually by comparing the observed color with well-known concepts: milky white, light green, cherry red, etc. This feature is not always characteristic of minerals, since the colors of many of them vary greatly.

Often, the color is determined by the chemical composition of the mineral or the presence of various impurities in which there are chemical elements-chromophores (chromium, manganese, vanadium, titanium, etc.). The mechanism for the appearance of a particular color on gems is still not always clear, since the same chemical element can color different gems in different colors: the presence of chromium makes the ruby ​​red, and the emerald green.

Dash color

A more reliable diagnostic feature than the color of a mineral is the color of its powder, which is left when the tested mineral scratches the matte surface of a porcelain plate. In some cases, the color of the line coincides with the color of the mineral itself, in others it is completely different. So, in cinnabar, the color of the mineral and powder are red, and in brass-yellow pyrite, the line is greenish-black. The feature is given by soft and medium hard minerals, while hard ones only scratch the plate and leave grooves on it.

Color traits of minerals on a porcelain plate

Transparency

According to their ability to transmit light, minerals are divided into several groups:

• transparent(rock crystal, rock salt) - transmitting light, objects are clearly visible through them;
• translucent(chalcedony, opal) - objects, objects are poorly visible through them;
• translucent only in very thin plates;
• opaque- light is not transmitted even in thin plates (pyrite, magnetite).

Shine

Luster is the ability of a mineral to reflect light. There is no strict scientific definition of the concept of brilliance. Distinguish minerals with a metallic luster like polished minerals (pyrite, galena); with semi-metallic (diamond, glass, matte, oily, waxy, mother-of-pearl, iridescent, silky).

Cleavage

The phenomenon of cleavage in minerals is determined by the adhesion of particles inside crystals and is due to the properties of their crystal lattices. The splitting of minerals occurs most easily parallel to the densest networks of crystal lattices. These nets are most often best development manifest themselves in the external limitation of the crystal.

The number of cleavage planes in different minerals is not the same, up to six, and the degree of perfection of different planes may not be the same. There are the following types of cleavage:

• very perfect when the mineral is split without much effort into separate leaves or plates with smooth shiny surfaces - cleavage planes (gypsum).
• perfect, detected by a light impact on the mineral, which crumbles into pieces, limited only by smooth shiny planes. Uneven surfaces not along the cleavage plane are obtained very rarely (calcite splits into regular rhombohedrons of different sizes, rock salt into cubes, sphalerite into rhombic dodecahedrons).
• middle, which is expressed in the fact that when a mineral is struck, fractures are formed both along cleavage planes and along uneven surfaces (feldspars - orthoclase, microcline, labrador)
• imperfect. Cleavage planes in the mineral are difficult to detect (apatite, olivine).
• very imperfect. There are no cleavage planes in the mineral (quartz, pyrite, magnetite). At the same time, sometimes quartz (rock crystal) is found in well-cut crystals. Therefore, it is necessary to distinguish the natural faces of the crystal from the cleavage planes that appear when the mineral is fractured. The planes can be parallel to the edges and have a fresher look and a stronger shine.

kink

The nature of the surface formed during the fracture (split) of the mineral is different:

1. Smooth break if the split of the mineral occurs along cleavage planes, as, for example, in crystals of mica, gypsum, calcite.
2. step fracture obtained when there are intersecting cleavage planes in the mineral; it can be observed in feldspars, calcite.
3. uneven fracture characterized by the absence of shiny cleavage areas, as, for example, in quartz.
4. grainy fracture observed in minerals with a granular-crystalline structure (magnetite, chromite).
5. earthy fracture characteristic of soft and highly porous minerals (limonite, bauxite).
6. conchoidal- with convex and concave areas like those of shells (apatite, opal).
7. splintery(acicular) - an uneven surface with splinters oriented in one direction (selenite, chrysotile asbestos, hornblende).
8. Hooked– hooked irregularities appear on the split surface (native copper, gold, silver). This type of fracture is typical for malleable metals.

Smooth fracture on mica Rough fracture on rose quartz Stepwise fracture on halite. © Rob Lavinsky Grainy fracture of chromite. © Piotr Sosonovski
Earthy fracture of limonite Conchoidal fracture on flint Splinter fracture on actinolite. © Rob Lavinsky Hooked fracture in copper

Hardness

Mineral hardness- this is the degree of resistance of their outer surface to the penetration of another, harder mineral and depends on the type of crystal lattice and the strength of the bonds of atoms (ions). The hardness is determined by scratching the surface of the mineral with a fingernail, knife, glass or minerals with a known hardness from the Mohs scale, which includes 10 minerals with gradually increasing hardness (in relative units).

The relativity of the position of minerals in terms of the degree of increase in their hardness is visible when compared: accurate determinations of the hardness of diamond (hardness on a scale of 10) showed that it is more than 4,000 times higher than that of talc (hardness - 1).

Mohs scale

The main mass of minerals has a hardness of 2 to 6. Harder minerals are anhydrous oxides and some silicates. When determining a mineral in a rock, it must be ensured that it is the mineral that is being tested and not the rock.

Specific gravity

The specific gravity varies from 0.9 to 23 g/cm 3 . For most minerals, it is 2 - 3.4 g / cm 3, ore minerals and native metals have the highest specific gravity of 5.5 - 23 g / cm 3. The exact specific gravity is determined in the laboratory, and in normal practice - by "weighing" the sample on the hand:

1. Light (with a specific gravity of up to 2.5 g / cm 3) - sulfur, rock salt, gypsum and other minerals.
2. Medium (2.6 - 4 g / cm 3) - calcite, quartz, fluorite, topaz, brown iron ore and other minerals.
3. With a large specific gravity (more than 4). These are barite (heavy spar) - with a specific gravity of 4.3 - 4.7, sulfur ores of lead and copper - a specific gravity of 4.1 - 7.6 g / cm 3, native elements - gold, platinum, copper, iron, etc. .d. with a specific gravity from 7 to 23 g / cm 3 (osmic iridium - 22.7 g / cm 3, platinum iridium - 23 g / cm 3).

magnetism

The property of minerals to be attracted by a magnet or to deflect a magnetic compass needle is one of the diagnostic features. Magnetite and pyrrhotite are highly magnetic minerals.

Malleability and brittleness

Malleable are minerals that change their shape when struck with a hammer, but do not crumble (copper, gold, platinum, silver). Fragile - crumble into small pieces on impact.

Electrical conductivity

The electrical conductivity of minerals is the ability of minerals to conduct electricity Under the influence electric field. Otherwise, minerals are referred to as dielectrics, i.e. non-conductive.

Flammability and odor

Some minerals catch fire from a match and create characteristic odors (sulfur - sulfur dioxide, amber - an aromatic smell, ozocerite - a suffocating smell of carbon monoxide). The smell of hydrogen sulfide appears when striking marcasite, pyrite, when grinding quartz, fluorite, calcite. When pieces of phosphorite are rubbed against each other, the smell of burnt bone appears. Kaolinite, when wetted, acquires the smell of a stove.

Taste

Taste sensations are caused only by minerals that are well soluble in water (halite - salty taste, sylvin - bitterly salty).

Roughness and oiliness

Fatty, slightly smearing are talc, kaolinite, rough - bauxite, chalk.

Hygroscopicity

This is the property of minerals to be moistened by attracting water molecules from environment, including from air (carnallite).

Some minerals react with acids. To identify minerals that are salts of carbonic acid in chemical composition, it is convenient to use the reaction of boiling them with weak (5 - 10%) hydrochloric acid (calcite, dolomite).

Radioactivity

Radioactivity can serve as an important diagnostic feature. Some minerals containing radioactive chemical elements (such as uranium, thorium, tantalum, zirconium, thorium) often have significant radioactivity, which is easy to detect with household radiometers. To check radioactivity, the background value of radioactivity is first measured and recorded, then a mineral is placed on the detector of the device. An increase in readings by more than 15% indicates the radioactivity of the mineral. Radioactive minerals are: abernathyite, bannerite, gadolinite, monazite, orthite, zircon, etc.

glow

glowing fluorite

Some minerals, which do not glow by themselves, begin to glow under various special conditions (heating, irradiation with x-rays, ultraviolet and cathode rays; when broken and even scratched). There are the following types of luminescence of minerals:

1. Phosphorescence - the ability of a mineral to glow for minutes and hours after exposure to certain rays (willemite glows after exposure to short ultraviolet rays).
2. Luminescence - the ability to glow at the moment of irradiation with certain rays (scheelite glows blue when irradiated with ultraviolet and rays).
3. Thermoluminescence - glow when heated (fluorite glows purple-pink).
4. Triboluminescence - glow at the moment of scratching with a knife or splitting (corundum).

Asterism

Asterism or star effect

Asterism, or the effect of starryness, is inherent in few minerals. It consists in the reflection (diffraction) of light rays from inclusions in the mineral, oriented along certain crystallographic directions. The best representatives of this property are star sapphire and star ruby.

In minerals with a fibrous structure (cat's eye), a thin strip of light is observed that can change its direction when the stone is turned (iridescence). The play of light on the surface of the opal or the shining peacock colors of the labrador are explained by the interference of light - the mixing of light rays when they are reflected from the layers of packed silica balls (in opal) or from the thinnest lamellar crystalline ingrowths (labrador, moonstone).

Invented in the time of Cleopatra, mineral makeup has, in fact, been around for nearly a thousand years. Experts sing praises to her, because she evens out the tone of the face, does not clog pores, does not cause inflammation and makes us more beautiful.

What other properties does mineral makeup have and why is it so useful for our skin, experts told Passion.ru - art director of Jane Iredale in Russia Yulia Kurolenko, training manager of the cosmetic line St. Barth (LIGNE ST BARTH) Tatyana Zakharova and trainer for Oriflame products Anastasia Furka .

The difference between mineral and mineral cosmetics

Beneficial features mineral cosmetics opened in Ancient Egypt. Especially for Cleopatra, shadows were made from copper derivatives, similar to bright green paste, and loyal subjects of the queen used crushed lead to line their eyes. In the Middle Ages, ladies used white lead to make their faces look aristocratic (a blush is a privilege of peasant women!).

Over time, both the former equipment and raw materials were forgotten. The fact that such mineral makeup was extremely harmful to the body, even poisonous, also played a role. Mineral cosmetics were revived to life about 40 years ago, when scientists discovered that mica, crushed to extremely small particles, perfectly replaces powder, provides good coverage and evens out the tone of the face. Thanks to natural pigments and weightless textures, mineral makeup has become very popular among both professional makeup artists and ordinary girls.

Nowadays, with all the availability of various cosmetic lines, collections marked “mineral” do not give up their positions. Especially in last years when the desire for naturalness, naturalness and merging with nature grew into a real boom.

Now many cosmetic companies add minerals to their lines, hoping that jars containing gifts from the bottom of the sea will produce a miraculous effect, but such cosmetics cannot be called mineral.

True mineral makeup has a dry, powdery, pressed texture and is non-GMO. As soon as they get into action oils , emulsifiers, thickeners and preservatives necessary for the production of foundations, liquid shadows, blushes and lip glosses , such cosmetics immediately become in the ranks containing minerals, and are not completely natural.

Homemade cosmetics recipes

9 best mascaras of spring

Effective Nutricosmetics

Manufacturers of mineral cosmetics "grow" raw materials for its creation in laboratory conditions, subject it to thorough purification (for example, from heavy metals) and synthesis. As part of the finished lines, crushed minerals are present in a sterilized form and do not require the introduction of additional preservatives and parabens. Even the powder in such collections of cosmetics does not contain talc. If the products include a high content of the aqueous phase, then natural substances are used for their conservation.

Typically, in the composition of the lines of mineral cosmetics, you can find the following components:

• titanium dioxide (TiO2) A proven physical sunscreen, most commonly found in beach sand. In cosmetics, it works like antioxidant and reflects UV radiation.
• zinc oxide (Zinc oxide (ZnO))- derived from a mineral called zincite. Zinc oxide works as a sunscreen and has an antimicrobial disinfecting effect.
• mica- mineral silica, the primary component of granites. In all types of mineral cosmetics, a special type of mica is used - sericite. By itself, this material is colorless, therefore it does not affect the color of the final product, but depending on the degree of processing, it creates different effects in cosmetics. Large particles of mica work like a shimmer, the crushed product makes the coating matte and more resistant, as mica absorbs sebum and excess moisture well.
• Boron nitride (BN)- Produced as a white, silky powder, which gives a slight radiance and gloss to the skin. This substance is also called soft focus for its ability to scatter light.
• iron oxide (Iron oxides (Fe203))-Known as common rust on iron. This material is synthesized in the laboratory, in cosmetics it plays the role of a pigment, in company with mica, crushed precious and semi-precious stones, it gives shine, radiance and color to the texture.

4 properties of mineral makeup

1. Does not cause inflammation

Mineral makeup is by nature considered hypoallergenic . Its components do not react with the components of other cosmetic lines and skin lipids, and therefore cannot cause allergic reactions.

2. Has healing properties

Mineral makeup does not clog pores and does not cause inflammation, but, on the contrary, has a bactericidal and regenerating effect on the skin, due to the content of the same zinc oxide. Therefore, plastic surgeons and dermatologists recommend mineral cosmetics even after surgeries, laser therapy and skin resurfacing.

Since mineral lines have anti-inflammatory and soothing properties, experts recommend using them to create makeup for acne patients and rosacea (demodectic mange).

3. Protects from the sun

Zinc oxide and titanium dioxide are natural sunscreens. Their degree of protection is equivalent to SPF 15. These components are moisture resistant, absorb excess sebum, providing make-up durability - and this is a real gift for owners of oily skin.

But it is very important to remember that mineral cosmetics do not protect against all UV rays, therefore, when in the active sun, apply a protective cream.

4. Lies flat

Mineral makeup does not contain talc, so it does not clog into pores, wrinkles and creases, it lays down in an even layer, emphasizing only the dignity of the skin and adding a healthy glow to it.

Spectrum of colors

Mineral makeup is usually blamed for a limited range of shades. Indeed, the color scheme is inferior to the usual decorative lines, because natural minerals are used for production, and they have their own unique color.

However, the mineral lines, usually presented in a loose form, give you a huge field for experimentation - they allow you to mix the colors of shadows, blush, powders and get new tones.

How to apply mineral makeup

1. Before applying mineral makeup, you need to thoroughly moisturize the skin so that there are no roughness and peeling.

2. Then, in order for the shadows, powder and blush to lie better, it is necessary to work out the relief of the face with a primer, which will also serve as a good fixer for cosmetics.

3. In order to apply decorative mineral makeup, you should get a set of brushes . For example, powder is applied to the face with a special kabuki brush, making circular movements.

4. Mineral makeup can be mixed with regular decorative lines. Experts even recommend doing this to get tonal means , cream shadows and lipsticks of unique shades.

Your beauty assistants:

1. Algo-mineral corrector Giordani Gold Oriflame ,
2. Eyeshadow Idyllic Metallic Ga-De ,
3. Blush bronzer Jane Iredale ,
4. Powder Priori CoffeeBerry Natureceuticals Natural Perfecting Minerals Foundation SPF15 ,
5. Shadows Era Minerals ,
6. Compact powder Even Skintone Compact Ultraceuticals ,
7. Foundation Liquid Minerals™ A Foundation Amber Jane Iredale .

DETERMINER OF MINERALS

INTRODUCTION

This guide is intended to assist students in studying short course engineering geology, independent work by definition of minerals. The determinant is compiled in the form of a table, which simplifies the choice of a mineral corresponding to a set of properties determined by the student. Properties of minerals and characteristics of classification groups are given in special sections.

1. Determination of the brilliance of a mineral.

2. Determination of hardness.

3. Determining the color of the line.

4. Selection of suitable minerals according to the vertical graphs of certain properties of points 1, 2, 3.

5. Identification by defining other properties along the horizontal lines of the determinant.

At the end of the manual is placed alphabetical index 116 minerals described in it and their formulas are given.

I. PROPERTIES AND GENESIS OF MINERALS

Basic properties of minerals

Minerals are relatively concrete and fairly stable chemical compounds and native elements, characterized by a strictly constant internal structure. Usually, minerals include natural formations that have arisen as a result of physicochemical processes in the bowels and on the surface of the earth's crust. However, gems grown in laboratories and factories, mineral formations obtained by modeling geological processes, and pearls grown as aquaculture cannot be ignored.

Up to 4000 minerals are known today. Of course, there are different systematics. The manual uses the principle based on the allocation of classes, subclasses, groups of fractional chemical classification units. The division based on the chemical constitution reflects many of the properties of minerals that allow them to be diagnosed. The guide lists the main properties of the most typical representatives of native elements, sulfides, sulfates, halides, fluorides, phosphates, carbonates, oxides and silicates.

The main properties are inherent in all minerals, so the diagnosis is based on differences in the characteristics of these features. In addition, diagnostics is aided by additional features that reflect the specific properties that are not inherent in all, and even one of a kind, minerals, but allow them to be quickly and unambiguously identified. The determinant takes into account both basic (chemistry, structure, mineral aggregates, hardness, density, cleavage, fracture, color, trait, luster, genesis) and additional (magnetic and electrical properties, hygroscopicity, smell, taste, flammability, elasticity, malleability, radioactivity) properties and information on the practical use of minerals.

The structure of minerals. In nature, there are solid, liquid and gaseous mineral formations. Hard minerals can be crystalline and amorphous. Crystalline crystals consist of many identical structural elements that form an ordered spatial (crystal) lattice. There are atomic, ionic and molecular types of lattices, which determine anisotropy(different properties), isotropy (same properties) of crystals and their ability to self-cut. Crystals - both natural and artificial - are shaped like polyhedrons. They can be isotropic and anisotropic. Amorphous minerals are always isotropic. The ability of substances with the same chemical composition to crystallize in different forms is called polymorphism (multiformity). For example: diamond and graphite, pyrite and marcasite, calcite and aragonite. The different structure of polymorphic varieties explains their different properties. Some substances of different chemical composition can form similar crystallographic forms. Such substances can create mixed forms containing the original components in different proportions. This phenomenon is called isomorphism, and mixtures are called isomorphic. An example is feldspars, the isomorphic series of which is formed by mixing albite and anorthite molecules.

Under natural conditions, not quite regular crystalline forms most often grow, having some defects, but with any flaws, the angles between the corresponding faces of crystals of the same substance remain the same and constant. This law of constancy of facet angles makes it possible to establish the ideal shape of crystals and accurately diagnose the smallest mineral grains.

Different degrees of symmetry of crystals are explained by different combinations of planes, axes of centers and symmetry in them. There can be 32 such combinations, and they are called classes(or types) of symmetry. The latter are combined into 7 systems, or syngonies: cubic, tetragonal, hexagonal, rhombic, trigonal, monoclinic and triclinic. Cubic crystals have higher symmetry: their simplest element is a cube, they are isotropic. Crystals of hexagonal, tetragonal and trigonal systems are characterized by middle symmetry. They have a columnar, columnar, needle, leafy, tabular, lamellar habit(appearance) and six-, four- and trihedral sections (respectively) perpendicular to the long axis. Anisotropy is expressed in the difference in the main properties along the long and short axes. The rhombic, monoclinic and triclinic syngonies belong to inferior symmetry group. They are characterized by very diverse shapes with anisotropic properties. In rhombic crystals, the cross section perpendicular to the long axis has the shape of a rhombus.

Natural mineral forms (clusters). Natural accumulations of mineral grains, or crystals, are commonly called mineral aggregates. They can be mono- and polymineral, those. composed of one or more minerals. The form of mineral aggregates depends on their composition and formation conditions.

A group of crystals grown on a common base forms Druse. A druse with small intergrown crystals oriented in one direction is called brush. These forms are formed during the crystallization of minerals in the voids of rocks (quartz, calcite, gypsum). have the same genesis secretions- mineral formations, partially or completely filling cavities and growing from the periphery to the center. Secretions can form both amorphous (chalcedony) and crystalline (quartz, calcite) minerals. Large secretions are called geodes, small - tonsils.

Nodular formations that have arisen in loose sedimentary formations at the bottom of ancient and modern reservoirs as a result of the contraction of mineral matter around foreign crystallization centers are called nodules. The concretions grow from the center to the periphery, they can be radially radiant and concentric in structure. Their shapes and sizes are very different. The smallest nodules are oolites (calcite, aragonite, phosphorite, flint, siderite, ferromanganese nodules of the modern ocean floor).

In voids, including caves, sinter forms are widespread. They can have the most varied size and composition (calcite, malachite, clay minerals, ice, etc.). This is first of all stalactites, stalagmites and stalagnates, reniform and grape-shaped formations of caves.

With rapid crystallization in small cracks and clay of salts falling from groundwater, thin branched tree-like formations are formed - dendrites. Dendrites of native copper, ferruginous and manganese compounds, etc. are most often found.

Mineral aggregates of disordered grains and crystals are divided into coarse (more than 3 mm), medium (1–3 mm) and fine-grained (less than 1 mm). Their appearance can be not only granular (crystalline), but also lamellar, foliose, columnar, banded, fibrous, oolitic, etc. It is the nature of mineral aggregates that determines the structural and textural features of rocks. Aggregates of grains indistinguishable under a magnifying glass are called cryptocrystalline; soft, dirty hands, reminiscent of loose soil - earthy(kaolin, bauxite, limonite, etc.).

False forms that do not correspond to the true habitus of the substance composing them are called pseudomorphoses. In accordance with the genesis, pseudomorphoses of transformation are distinguished, or metamorphosis, such as the formation of limonite after pyrite; displacement (chalcedony, flint on calcite), execution (opal, limonite on wood).

Physical Properties minerals determine a set of its main features, which should include: hardness, density, cleavage, fracture, color, streak, gloss.

Hardness, or fracture resistance in diagnostics, is determined by scratching one mineral with another. In this way, they find out which mineral is harder, i.e. determine relative hardness. Definitions are made on the 10-point F. Mohs scale, consisting of 10 minerals, in which each subsequent mineral is a point harder than the previous one and therefore scratches it. Below is the F. Mohs scale with some practical recommendations.

1. Talc (scraped off with a fingernail).

2. Gypsum (scratched with a fingernail).

3. Calcite (scraped off with a knife).

4. Fluorite (easily scratched with a knife).

5. Apatite (hard to scratch with a knife).

6. Orthoclase (difficult to scratch with glass).

7. Quartz, (not scratched by glass).

8. Topaz, (leaves a scratch on the knife and glass).

9. Corundum, (leaves a scratch on the knife and glass).

10. Diamond, (leaves a scratch on the knife and glass).

When determining hardness, a scratch should not be confused with a line. From the features, the dust of the rock is completely erased with a finger. It must be remembered that anisotropic minerals have different hardness in different directions, and cryptocrystalline, porous and powdery masses are always softer than crystals with a good cut (hematite ocher - 1, hematite crystal - 6).

Density (specific gravity)- always reflects the chemical composition and structure of the mineral. It is determined approximately by “weighing” the mineral in the palm of your hand. Usually there are three weight categories: light (up to 3 g / cm 3), medium (3-4 g / cm 3) and heavy (more than 4 g / cm 3) minerals. With a specific gravity of more than 10 g/cm, one speaks of very heavy minerals. These include native gold, silver, platinum, mercury. The heaviest mineral known on Earth is osmium iridium, which has a density of 23 g/cm3. Most of minerals that make up the earth's crust are light and medium minerals.

Cleavage- this is the ability of minerals to split (split) along parallel, even, shiny surfaces, called cleavage planes. Cleavage is a property of exclusively crystalline minerals. The cleavage plane corresponds to the face of the crystal. There are the following types of cleavage:

Very perfect - the mineral is easily split into leaves, plates (mica, talc, lamellar gypsum);

Perfect - when struck with a hammer, fragments are formed, limited by cleavage planes (calcite, halite);

Medium - fragments are limited by both flat and uneven boundaries (orthoclase, augite);

Imperfect - cleavage planes are rarely found (apatite, olivine);

Very imperfect - cleavage planes are practically absent (quartz, pyrite, magnetite).

kink are split surfaces oriented contrary to cleavage. There are conchoidal (chalcedony, flint, quartz), splintery (selenite, asbestos), granular (rocks), earthy (bauxite, limonite, stepped (orthoclase, galena) and other fracture surfaces.

Color cannot be considered the main diagnostic feature of minerals, because it is changeable and depends on many factors. These are structural features, and the presence of dyes (chromophores), mechanical impurities, cracks and voids. The color is also controlled by environmental parameters such as temperature, humidity, etc. The perception of color by the eyes is also not unambiguous. However, a number of minerals have a permanent color. For example, galena is always gray, vermilion is red, malachite is green, lapis lazuli is blue, and so on. Impurities, on the other hand, which cause differences in color and shades, very often provide information about the chemical composition. For example, in the group of garnets, magnesium-aluminum pyrope is dark red, calcium-aluminum grossular is light green, calcium-iron andradite is brownish-green, etc. (see: Key. "Grenades", No. 75). Describing the color of the mineral, one should characterize the main color, its depth and shade. For example: dark gray with a bluish tint (for molybdenite). In mineralogy, non-standard color characteristics such as “cochineal red”, “pistachio”, “brass yellow”, “straw yellow”, etc. are often used. However, despite the imagery of such definitions, it is better to reduce their use to a minimum.

Dash (dash color)- this is a trace that remains on an unglazed porcelain plate (biscuit), if you draw on it with a mineral. In some cases, it coincides with the color of the mineral in the piece (cinnabar, magnetite, malachite, etc.). But many minerals are characterized by sharp differences in the color of the line and the piece (pyrite, hematite). A line is a more permanent diagnostic feature than a color in a piece.

Color and line should be determined in a fresh fracture.

Shine reflects how internal structure, and the nature of the reflective surface of the mineral. Minerals with a metallic sheen are easily distinguished. Minerals with a metallic and metallic luster most often have a black or very dark line (magnetite, galena, graphite); minerals with a white and colored streak usually have a non-metallic luster (gypsum, sulfur, cinnabar). In the group of minerals with a metallic sheen, the exceptions are: native gold, copper, silver, platinum, chalcopyrite and faded ores. Having a metallic luster, they give a color line: gold - greenish, silver - silver-white, copper - copper-red, chalcopyrite - greenish, faded ores - dark brown. Non-metallic luster is divided into: polymetallic (the mineral has a metallic luster, but its line and powder are colored), diamond, glass, fat, silky, mother-of-pearl, matte, etc.

Minerals are chemical compounds (with the exception of native elements). However, even colorless, optically transparent samples of these minerals almost always contain small amounts of impurities.

Natural solutions or melts from which minerals crystallize usually consist of many elements. In the process of formation of compounds, a few atoms of less common elements can replace the atoms of the main elements. Such a substitution is so common that the chemical composition of many minerals only very rarely approaches that of the pure compound.

For example, the composition of the widespread rock-forming mineral olivine varies within the compositions of two so-called. final members series: from forsterite, magnesium silicate Mg2SiO4, to fayalite, iron silicate Fe2SiO4. The ratios of Mg:Si:O in the first mineral and Fe:Si:O in the second are 2:1:4.

In olivines of intermediate composition, the values ​​of the ratios are the same; (Mg + Fe):Si:O is equal to 2:1:4, and the formula is written as (Mg,Fe)2SiO4. If the relative amounts of magnesium and iron are known, then this can be reflected in the formula (Mg0.80Fe0.20)2SiO4, from which it can be seen that 80% of the metal atoms are magnesium, and 20% are iron.

Structure. All minerals, with the exception of water (which, unlike ice, is usually not classified as a mineral) and mercury, are present at ordinary temperatures solid bodies. However, if water and mercury are strongly cooled, they solidify: water - at 0 ° C, and mercury - at -39 ° C. At these temperatures, water molecules and mercury atoms form a characteristic regular three-dimensional crystalline structure (the terms "crystalline" and "solid ” in this case are almost equivalent).

Thus, minerals are crystalline substances, the properties of which are determined by the geometric arrangement of their constituent atoms and the type of chemical bond between them. The unit cell (the smallest subdivision of a crystal) is made up of regularly spaced atoms held together by electronic bonds.

These tiny cells, endlessly repeating in three-dimensional space, form a crystal. The sizes of elementary cells in different minerals are different and depend on the size, number and mutual arrangement of atoms within the cell. Cell parameters are expressed in angstroms or nanometers (1 =10 -8 cm = 0.1 nm).

The elementary cells of a crystal put together densely, without gaps, fill the volume and form a crystal lattice. Crystals are subdivided according to the symmetry of the unit cell, which is characterized by the ratio between its edges and corners.

Usually, 7 syngonies are distinguished (in order of increasing symmetry): triclinic, monoclinic, rhombic, tetragonal, trigonal, hexagonal and cubic (isometric). Sometimes the trigonal and hexagonal systems are not separated and are described together under the name of the hexagonal system.

The syngonies are subdivided into 32 crystal classes (types of symmetry), including 230 space groups. These groups were first identified in 1890 by the Russian scientist E.S. Fedorov. Using X-ray diffraction analysis, the dimensions of the elementary cell of the mineral, its syngony, symmetry class and space group are determined, and the crystal structure is deciphered, i.e. mutual arrangement in three-dimensional space of the atoms that make up the elementary cell.

GEOMETRIC (MORPHOLOGICAL) CRYSTALOGRAPHY

Crystals with their flat, smooth, shiny facets have long attracted the attention of man. Since the emergence of mineralogy as a science, crystallography has become the basis for the study of the morphology and structure of minerals. It was found that the crystal faces have a symmetrical arrangement, which makes it possible to attribute the crystal to a certain syngony, and sometimes to one of the classes (symmetries) (see above).

X-ray studies have shown that the external symmetry of the crystals corresponds to the internal regular arrangement of atoms. The sizes of mineral crystals vary over a very wide range - from giants weighing 5 tons (the mass of a well-formed quartz crystal from Brazil) to so small that their faces can only be distinguished under an electron microscope.

The shape of a crystal of even the same mineral in different samples may differ slightly; for example, quartz crystals are nearly isometric, acicular or flattened. However, all quartz crystals, large and small, pointed and flat, are formed by repeating identical unit cells.

If these cells are oriented in a certain direction, the crystal has an elongated shape, if in two directions to the detriment of the third, then the shape of the crystal is tabular. Since the angles between the corresponding faces of the same crystal have a constant value and are specific for each mineral species, this feature is necessarily included in the mineral characteristic.

Minerals represented by individual well-cut crystals are rare. Much more often they occur in the form of irregular grains or crystalline aggregates. Often, a mineral is characterized by a certain type of aggregate, which can serve as a diagnostic feature. There are several types of aggregates.

Dendritic branching aggregates similar to fern leaves or moss and are characteristic, for example, of pyrolusite. Fibrous aggregates consisting of tightly packed parallel fibers are typical of chrysotile and amphibole-asbestos.

colloform aggregates, which have a smooth rounded surface, are built from fibers that extend radially from a common center. Large rounded masses are mastoid (malachite), while smaller ones are kidney-shaped (hematite) or grape-shaped (psilomelan).

Scale aggregates, consisting of small lamellar crystals, are characteristic of mica and barite.

stalactites- Sag-drop formations hanging in the form of icicles, tubes, cones or "curtains" in karst caves. They result from the evaporation of mineralized water seeping through limestone fissures and are often composed of calcite (calcium carbonate) or aragonite.

Oolites- aggregates consisting of small balls and resembling fish caviar are found in some calcite (oolitic limestone), goethite (oolitic iron ore) and other similar formations.

After the accumulation of X-ray data and their comparison with the results of chemical analyzes, it became obvious that the features of the crystal structure of the mineral depend on its chemical composition. Thus the foundations were laid new science- crystal chemistry.

Many seemingly unrelated properties of minerals can be explained on the basis of their crystal structure and chemical composition. Some chemical elements (gold, silver, copper) are found in native, i.e. clean, kind. They are built from electrically neutral atoms (unlike most minerals, whose atoms carry an electrical charge and are called ions). An atom with a lack of electrons is positively charged and is called a cation; an atom with an excess of electrons has a negative charge and is called an anion.

The attraction between oppositely charged ions is called ionic bonding and is the main binding force in minerals. With another type of bond, the outer electrons revolve around the nuclei in common orbits, connecting the atoms to each other. A covalent bond is the strongest type of bond.

Minerals with a covalent bond usually have a high hardness and melting point (for example, diamond). A much smaller role in minerals is played by the weak van der Waals bond that arises between electrically neutral structural units.

The binding energy of such structural units (layers or groups of atoms) is unevenly distributed. The van der Waals bond provides attraction between oppositely charged sites in larger structural units. This type of bond is observed between layers of graphite (one of the natural forms of carbon) formed due to the strong covalent bond of carbon atoms. Due to the weak bonds between the layers, graphite has a low hardness and a very perfect cleavage parallel to the layers. Therefore, graphite is used as a lubricant.

Oppositely charged ions approach each other until the distance at which the repulsive force balances the attractive force. For any particular cation-anion pair, this critical distance is equal to the sum of the "radii" of the two ions. By determining the critical distances between different ions, it was possible to determine the size of the radii of most ions (in nanometers, nm). Because most minerals have ionic bonds, their structures can be visualized as contiguous balls.

The structures of ionic crystals depend mainly on the magnitude and sign of the charge and the relative sizes of the ions. Since the crystal as a whole is electrically neutral, the sum of the positive charges of the ions must be equal to the sum of the negative ones. In sodium chloride (NaCl, the mineral halite), each sodium ion has a charge of +1, and each chloride ion has a charge of -1 (Fig. 1), i.e. Each sodium ion corresponds to one chloride ion. However, in fluorite (calcium fluoride, CaF2), each calcium ion has a charge of +2, and each fluorine ion has a charge of -1. Therefore, to maintain the overall electrical neutrality of fluorine ions, there should be twice as much as calcium ions (Fig. 2).

The possibility of their entry into a given crystal structure also depends on the size of the ions. If the ions are the same size and packed in such a way that each ion is in contact with 12 others, then they are in proper coordination.

There are two ways to pack balls of the same size (Fig. 3): cubic closest packing, which generally leads to the formation of isometric crystals, and hexagonal closest packing, which forms hexagonal crystals. As a rule, cations are smaller in size than anions, and their sizes are expressed in fractions of the radius of the anion, taken as unity.

Usually, the ratio obtained by dividing the radius of the cation by the radius of the anion is used. If the cation is only slightly smaller than the anions with which it is combined, it can come into contact with eight anions surrounding it, or, as is commonly said, is in eightfold coordination with respect to the anions, which are located, as it were, at the vertices of the cube around it. This coordination (also called cubic) is stable at ratios of ionic radii from 1 to 0.732 (Fig. 4a).

With a smaller ratio of ionic radii, eight anions cannot be stacked so as to touch the cation. In such cases, the packing geometry allows six-fold coordination of cations with anions located at six vertices of the octahedron (Fig. 4b), which will be stable at ratios of their radii from 0.732 to 0.416.

With a further decrease in the relative size of the cation, a transition occurs to quadruple, or tetrahedral, coordination, which is stable at ratios of radii from 0.414 to 0.225 (Fig. 4c), then to triple coordination within the range of ratios of radii from 0.225 to 0.155 (Fig. 4c). d) and double - with ratios of radii less than 0.155 (Fig. 4e).

Although other factors also determine the type of coordination polyhedron, for most minerals the principle of the ratio of ion radii is one of the effective means of predicting the crystal structure.

Rice. 4. COORDINATION POLYHEDRA are formed when anions are placed around cations. Possible types of arrangement depend on the relative sizes of anions and cations. Allocate the following types coordination: a - cubic, or eight-dimensional coordination; b - octahedral, or gear; c - tetrahedral, or quadruple; g - triangular, or triple coordination; e - double coordination.

Minerals of completely different chemical compositions can have similar structures that can be described using the same coordination polyhedra. For example, in sodium chloride NaCl, the ratio of the radius of the sodium ion to the radius of the chloride ion is 0.535, indicating an octahedral, or six-fold, coordination.

If six anions cluster around each cation, then to keep the ratio of cations to anions equal to 1:1, there must be six cations around each anion. This forms a cubic structure known as a sodium chloride type structure.

Although the ionic radii of lead and sulfur differ sharply from the ionic radii of sodium and chlorine, their ratio also predetermines six-fold coordination, therefore PbS galena has a sodium chloride type structure, i.e. halite and galena are isostructural.

Impurities in minerals are usually present in the form of ions that replace the ions of the "host" mineral. Such substitutions greatly affect the size of the ions. If the radii of two ions are equal or differ by less than 15%, they are easily mutually substituted. If this difference is 15-30%, such substitution is limited; with a difference of more than 30%, substitution is practically impossible.

There are many examples of pairs of isostructural minerals with similar chemical composition between which ion substitution occurs. Thus, siderite (FeCO3) and rhodochrosite (MnCO3) carbonates have similar structures, and iron and manganese can replace each other in any ratio, forming the so-called. solid solutions. Between these two minerals there is a continuous series of solid solutions. In other pairs of minerals, ions have limited possibilities for mutual substitution.

Since minerals are electrically neutral, the charge of the ions also affects their mutual substitution. If substitution occurs by an oppositely charged ion, then a second substitution must take place in some part of this structure, in which the charge of the substituting ion compensates for the violation of electrical neutrality caused by the first one. Such conjugate substitution is noted in feldspars - plagioclases, when calcium (Ca2+) replaces sodium (Na+) with the formation of a continuous series of solid solutions.

The excess positive charge arising as a result of the Ca2+ ion replacing the Na+ ion is compensated by the simultaneous substitution of silicon (Si4+) for aluminum (Al3+) in neighboring regions of the structure.

PHYSICAL PROPERTIES OF MINERALS

Although the main characteristics of minerals (chemical composition and internal crystal structure) are established on the basis of chemical analyzes and X-ray diffraction, they are indirectly reflected in properties that are easily observed or measured. To diagnose most minerals, it is enough to determine their luster, color, cleavage, hardness, and density.

Shine- a qualitative characteristic of the light reflected by the mineral. Some opaque minerals reflect light strongly and have a metallic sheen. This is typical for ore minerals, for example, galena (lead mineral), chalcopyrite and bornite (copper minerals), argentite and acanthite (silver minerals).

Most minerals absorb or transmit a significant portion of the light incident on them and have a non-metallic luster. Some minerals have a luster that transitions from metallic to non-metallic, which is called semi-metallic.

Minerals with non-metallic luster are usually light-colored, some of them are transparent. Often there are transparent quartz, gypsum and light mica. Other minerals (for example, milky white quartz) that transmit light, but through which objects cannot be clearly distinguished, are called translucent. Minerals containing metals differ from others in terms of light transmission.

If light passes through a mineral, at least in the thinnest edges of the grains, then it is, as a rule, non-metallic; if the light does not pass, then it is ore. There are, however, exceptions: for example, light-colored sphalerite (zinc mineral) or cinnabar (mercury mineral) are often transparent or translucent.

Minerals vary in quality characteristics non-metallic luster. Clay has a dull earthy sheen. Quartz on the edges of crystals or on fracture surfaces is glassy, ​​talc, which is divided into thin sheets along cleavage planes, is mother-of-pearl. Bright, sparkling, like a diamond, the brilliance is called diamond.

When light falls on a mineral with a non-metallic luster, it is partially reflected from the surface of the mineral, and partially refracted at this boundary. Each substance is characterized by a certain refractive index. Since this indicator can be measured with high accuracy, it is a very useful diagnostic feature of minerals.

The nature of the brilliance depends on the refractive index, and both of them depend on the chemical composition and crystal structure of the mineral. In general, transparent minerals containing heavy metal atoms are distinguished by high brilliance and a high refractive index. This group includes such common minerals as anglesite (lead sulfate), cassiterite (tin oxide) and titanite, or sphene (calcium and titanium silicate).

Minerals composed of relatively light elements can also have high luster and a high refractive index if their atoms are closely packed and held together by strong chemical bonds. A striking example is diamond, which consists of only one light element, carbon.

To a lesser extent, this is also true for the mineral corundum (Al2O3), whose transparent colored varieties - ruby ​​and sapphires - are precious stones. Although corundum is made up of light atoms of aluminum and oxygen, they are so tightly bound together that the mineral has a rather strong luster and a relatively high refractive index.

Some glosses (oily, waxy, matte, silky, etc.) depend on the state of the surface of the mineral or on the structure of the mineral aggregate; resinous luster is characteristic of many amorphous substances (including minerals containing radioactive elements uranium or thorium).

Color— a simple and convenient diagnostic feature. Examples include brass yellow pyrite (FeS2), lead gray galena (PbS), and silvery white arsenopyrite (FeAsS2). In other ore minerals with a metallic or semi-metallic luster, the characteristic color may be masked by the play of light in a thin surface film (tarnish). This is characteristic of most copper minerals, especially bornite, which is called "peacock ore" because of its iridescent blue-green tint, which quickly develops on a fresh fracture. However, other copper minerals are painted in well-known colors: malachite - in green, azurite - in blue.

Some non-metallic minerals are unmistakably recognized by the color due to the main chemical element (yellow - sulfur and black - dark gray - graphite, etc.). Many non-metallic minerals are composed of elements that do not provide them with a specific color, but they are known to have colored varieties, the color of which is due to the presence of impurities of chemical elements in small quantities, not comparable with the intensity of the color they cause. Such elements are called chromophores; their ions are distinguished by the selective absorption of light. For example, deep purple amethyst owes its color to an insignificant impurity of iron in quartz, and the deep green color of emerald is associated with a small content of chromium in beryl.

The coloration of normally colorless minerals may appear due to defects in the crystal structure (due to unoccupied positions of atoms in the lattice or the entry of foreign ions), which can cause selective absorption of certain wavelengths in the white light spectrum. Then the minerals are painted in complementary colors. Rubies, sapphires and alexandrites owe their coloration to precisely such lighting effects.

Colorless minerals can be colored by mechanical inclusions. Thus, a thin scattered dissemination of hematite gives quartz a red color, chlorite - green. Milky quartz is turbid with gas-liquid inclusions. Although the color of minerals is one of the most easily determined properties in the diagnosis of minerals, it must be used with caution as it depends on many factors.

Despite the variability in the color of many minerals, the color of the mineral powder is very constant, and therefore is an important diagnostic feature. Usually, the color of the mineral powder is determined by the line (the so-called “line color”) that the mineral leaves if it is drawn over an unglazed porcelain plate (biscuit). For example, the mineral fluorite can be colored in different colors, but its line is always white.

Cleavage. characteristic property minerals is their behavior when splitting. For example, quartz and tourmaline, whose fracture surface resembles a glass chip, have a conchoidal fracture. In other minerals, the fracture may be described as rough, jagged, or splintery.

For many minerals, the characteristic is not a fracture, but cleavage. This means that they split along smooth planes that are directly related to their crystal structure. The bonding forces between the planes of the crystal lattice can be different depending on the crystallographic direction.

If in some directions they are much larger than in others, then the mineral will split across the weakest bond. Since cleavage is always parallel to the atomic planes, it can be labeled with crystallographic directions. For example, halite (NaCl) has cube cleavage, i.e. three mutually perpendicular directions of a possible split.

Cleavage is also characterized by the ease of manifestation and the quality of the resulting cleavage surface. Mica has a very perfect cleavage in one direction, i.e. easily splits into very thin leaves with a smooth shiny surface. Topaz has perfect cleavage in one direction.

Minerals can have two, three, four or six cleavage directions, along which they are equally easy to crack, or several cleavage directions of varying degrees. Some minerals have no cleavage at all. Since cleavage as a manifestation of the internal structure of minerals is their invariable property, it serves as an important diagnostic feature.

Hardness- the resistance that the mineral provides when scratched. Hardness depends on the crystal structure: the more strongly the atoms in the structure of the mineral are bound together, the harder it is to scratch it. Talc and graphite are soft, lamellar minerals built from layers of atoms held together by very weak forces. They are greasy to the touch: when rubbing against the skin of the hand, the individual thinnest layers slip off. The hardest mineral is diamond, in which the carbon atoms are so tightly bound that it can only be scratched by another diamond.

At the beginning of the 19th century Austrian mineralogist F. Moos arranged 10 minerals in order of increasing hardness. Since then, they have been used as standards for the relative hardness of minerals, the so-called. Mohs scale.

MOHS HARDNESS SCALE

To determine the hardness of a mineral, it is necessary to identify the hardest mineral that it can scratch. The hardness of the studied mineral will be greater than the hardness of the mineral scratched by it, but less than the hardness of the next mineral on the Mohs scale.

Mineral	Relative hardness
orthoclase

To quickly determine the hardness, you can use the following, simpler, practical scale.

Bond strengths can vary with crystallographic direction, and since hardness is a rough estimate of these forces, it can vary in different directions. This difference is usually small, with the exception of kyanite, which has a hardness of 5 in the direction parallel to the length of the crystal, and 7 in the transverse direction. In mineralogical practice, it is also used to measure the absolute values ​​of hardness (the so-called microhardness) using a sclerometer device, which is expressed in kg / mm 2.

Density. The mass of atoms of chemical elements varies from hydrogen (the lightest) to uranium (the heaviest). Other things being equal, the mass of a substance consisting of heavy atoms is greater than that of a substance consisting of light atoms. For example, two carbonates, aragonite and cerussite, have a similar internal structure, but aragonite contains light calcium atoms, while cerussite contains heavy lead atoms. As a result, the mass of cerussite exceeds the mass of aragonite of the same volume.

Mass per unit volume of a mineral also depends on the packing density of atoms. Calcite, like aragonite, is calcium carbonate, but in calcite the atoms are less tightly packed, because it has a lower mass per unit volume than aragonite. Relative mass, or density, depends on the chemical composition and internal structure.

Density- this is the ratio of the mass of a substance to the mass of the same volume of water at 4 ° C. So, if the mass of a mineral is 4 g, and the mass of the same volume of water is 1 g, then the density of the mineral is 4. In mineralogy, it is customary to express density in g / cm3 .

Density is an important diagnostic feature of minerals and is easy to measure. The sample is first weighed in air and then in water. Since a sample immersed in water is subjected to an upward buoyancy force, its weight is less there than in air. The weight loss is equal to the weight of the water displaced. Thus, the density is determined by the ratio of the mass of the sample in air to the loss of its weight in water.

Pyro-electricity. Some minerals, such as tourmaline, calamine, etc., become electrified when heated or cooled. This phenomenon can be observed by pollinating the cooling mineral with a mixture of powders of sulfur and red lead. In this case, sulfur covers the positively charged areas of the mineral surface, and red lead - areas with a negative charge.

magnetism – this is the property of certain minerals to act on a magnetic needle or be attracted by a magnet. To determine the magnetism, a magnetic needle placed on a sharp tripod, or a magnetic horseshoe, a bar is used. It is also very convenient to use a magnetic needle or knife.

When testing for magnetism, three cases are possible:

a) when a mineral in its natural form (“by itself”) acts on a magnetic needle,

b) when the mineral becomes magnetic only after calcination in the reducing flame of a blowpipe

c) when the mineral neither before nor after calcination in a reducing flame exhibits magnetism. To ignite the reducing flame, you need to take small pieces of 2-3 mm in size.

Glow. Many minerals that do not glow by themselves begin to glow under certain special conditions (when heated, exposed to x-rays, ultraviolet and cathode rays, when broken, scratched, etc.).

There are phosphorescence, luminescence, thermoluminescence and triboluminescence of minerals.

Phosphorescence is the ability of a mineral to glow after being exposed to certain rays (willemite).

Luminescence - the ability to glow at the time of irradiation (scheelite when irradiated with ultraviolet and cathode beams, calcite, etc.).

Thermoluminescence - glow when heated (fluorite, apatite).

Triboluminescence - glow at the moment of scratching with a needle or splitting (mica, corundum).

Radioactivity. Many minerals containing elements such as niobium, tantalum, zirconium, rare earths, uranium, thorium often have quite significant radioactivity, easily detectable even by household radiometers, which can serve as an important diagnostic feature. To check for radioactivity, the background value is first measured and recorded, then the mineral is brought, possibly closer to the instrument's detector. An increase in readings by more than 10-15% can serve as an indicator of the radioactivity of the mineral.

Electrical conductivity. A number of minerals have significant electrical conductivity, which allows them to be unambiguously distinguished from similar minerals. Can be tested with a common household tester.

Text: Svetlana Rakutova

Is it possible to treat the body with ordinary mineral water, what are the healing properties of mineral water and how is mineral water useful for children?

Properties of mineral water

We love to drink mineral water not only because we like its taste, but also because we understand that drinking mineral water is good for health. The beneficial properties of mineral water are due to the fact that it contains dissolved minerals that are found in groundwater. The same properties are possessed by water, which is taken from springs or raised from village wells. Carbonated mineral water also contains natural gases, or it may be artificially carbonated with carbon dioxide. Different countries set different standards for the amount of minerals needed for bottled water to be called "mineral".

One of the most valuable properties of mineral water is the absence of extra calories. Drinking mineral water is a way to provide the body with useful trace elements without gaining weight. Carbonated mineral water usually contains calcium, magnesium, potassium and sometimes sodium. These are the most common minerals in groundwater. Some types of carbonated mineral water contain chromium, copper, zinc, iron, manganese, selenium and other beneficial trace elements, each of which has great importance for health. Mineral water is a better source of minerals than any other water, such as that taken from a well. In some countries with modern water filtration systems, people can drink it from the tap. But it, of course, cannot be compared in properties with mineral water. And in our country tap water most often contains fluorine and chlorine, which can adversely affect the health of many people.

If we compare the properties of mineral water with the properties of distilled water, then the latter does not contain minerals at all. Like many brands of filtered water sold in stores, it also has very little or no minerals.

The healing properties of mineral water

When talking about the healing properties of mineral water, they usually remember the content of a large amount of calcium in it. Mineral water can be an alternative source of calcium for people with lactose intolerance. Such people are unable to consume most dairy products due to their illness. But instead of milk, they can drink mineral water. Calcium in it, of course, is not as much as in dairy products, but still. Moreover, the absorption of calcium obtained from mineral water is quite comparable with the absorption of calcium from dairy products.

A very important healing property of mineral water is its ability to reduce cholesterol levels in the body. Drinking carbonated water can reduce the amount of low-density lipoprotein, the so-called "bad" cholesterol in the body, and vice versa, increase the amount of "good" cholesterol - high-density lipoprotein. These data are supported by studies conducted in 2004 on a group of older (postmenopausal) women who drank sodium-rich carbonated mineral water.

Finally, another healing property of mineral water is hydration, that is, moisturizing the body. An adult usually needs about 3 liters of water per day, and more on hot days or during active sports. At the same time, the average person does not think much about such issues and does not drink ordinary water so often during the day. And carbonated mineral water, encouraging a person with its taste, will provide the required level of hydration of the body.

Table mineral water

The composition of table mineral water depends very much on the specific brand. but General characteristics they certainly have. First of all, any table mineral water does not contain fat and calories. Many people don't consider the calorie content of drinks like coca-cola or fruit juices. Uncontrolled consumption of such drinks may well derail a weight loss program. Moreover, reducing the amount of "liquid calories" can lead to weight gain, in contrast to reducing the intake of calories from food. Here the choice is obvious in favor of table mineral water, the use of which will always keep calories under control.

Almost all brands of table mineral water, except for calcium and sodium, also contain magnesium. This trace mineral is essential for bone health, and it also supports the development of cells, muscle and nerve tissue. Ordinary table mineral water contains up to 41% of the daily recommended intake of magnesium. Remember that you should strive to ensure that the daily intake of magnesium and other trace elements is carried out not only from table mineral water, but also from food.

Mineral water for children

Parents face difficult choices when it comes to deciding on the healthiest drink to fit into a balanced diet for a child. Faced with a dense stream of advertising information offering thousands of different brands of delicious drinks for children, the child hardly agrees to drink plain water. It is impossible to convince a small child that this is good for health, the main thing for him is that it is “tasty”. However, plain mineral water for children is much healthier than sweet fruit sodas or milkshakes.

It is worth noting here that mineral water enriched with carbon dioxide is not at all useful for children. Carbonated water and carbonated soft drinks have a long-term effect negative impact on the health of the child. Manufacturers saturate carbonated mineral water for children not only with phosphorus and carbonic acid, to create bubbles, but also with various flavorings - various man-made sweeteners that are more harmful than ordinary sugar extracted from fruits. The use of carbonated mineral water for children for a long time leads to a decrease in the level of calcium in the child's body. This can weaken the roots of the teeth and cause plaque damage. And excess sugar puts children at risk of developing diabetes.