Checking clay with vinegar. Natural clay is a valuable material with useful properties. Clay modeling with children

Clay is one of the most famous and common materials used in construction. It is formed as a result of the destruction of clay rocks naturally or with the help of mechanical and biochemical influences in the course of evolution.

What is clay made of

This rock is rather complex and unstable, both in composition and in its characteristics. Pure clay, which does not contain impurities, consists of small mineral particles with a size of no more than 0.01 mm. They usually have a plate-like shape.

Such "clay" materials are complex compounds of aluminum, silicon and water. They not only include water in their structure (such water is called chemically bound), but also hold it in the form of interlayers between particles (such water is called physically bound).

If the material is wetted, water enters the space between the layers of the material, and as a result, they easily move in relation to each other. It is thanks to this feature that the clay has high plasticity.

Clay contains impurities of substances such as calcium carbonate, quartz, iron sulfide, iron hydroxide, magnesium oxide, calcium oxide, etc. Depending on the chemical composition, clay materials such as kaolinite, halloysite, illite and montmorillonite are distinguished.

Based on the purpose of the raw material, it is standardized depending on the percentage of iron oxides, quartz sand, and various impurities. The degree of refractoriness of a material depends on its alumina content. To make refractory products, clay is used, which contains at least 28% alumina.

This is what a clay sample looks like under a microscope:

Specifications and properties

Clay characteristics are determined by chemical and mineral composition and particle size.

The volumetric and specific weight of refractory ground clay is 1300-1400 kg / m3, chamotte - 1800 kg / m3, dry clay in powder - 900 kg / m3. The density of wet clay is 1600-1820 kg / m3, dry - about 100 kg / m3. The thermal conductivity of dry raw materials is 0.1-0.3 W / (m * K), wet - from 0.4 to 3.0 W / (m * K).

Basic properties:

getting into the water, the clay gets soaked, separated into separate particles and forms either a plastic mass or a suspension;
clay dough is very plastic, in its raw state it can take any shape. Plastic clays are called "greasy" because they feel like a greasy material to the touch. Clays with low plasticity are called "skinny". Bricks made from such clay quickly disintegrate and have poor strength;
after drying, the clay retains its shape, somewhat decreasing in volume, and as a result of firing it becomes hard, like a stone. It is thanks to this ability that it has long been one of the most popular materials for tableware production. Also, bricks are made from clay, which have high mechanical strength;
possesses stickiness and bonding ability;
saturated with a certain volume of water, the clay no longer allows water to pass through, that is, it is waterproof;
clay has hiding power. Therefore, in the old days it was widely used to whitewash stoves and walls of a house;
clay has a sorption capacity, that is, it absorbs substances dissolved in a liquid. This allows it to be used for the purification of oil products and vegetable fats.

The properties of the material ensure a long service life, but only if they are properly cared for and no mistakes were made during the manufacturing process.

Origin and extraction of clay

Clay can be of different origins - sedimentary or residual. Sedimentary rocks are formed when the weathering products are transferred to another location. They can be marine or continental.

Marine clays are formed in coastal areas, river deltas, lagoons, and on the shelves. Continental clays can be deluvial, proluvial, lacustrine, fluvial, or residual.

Residual rocks are formed when rocks are weathered at sea or on land. An example of continental residual clays is kaolin (white clay). Marine residues are usually bleaching materials.

How is mining

Most types of clay can be found easily because they are often found in nature, are shallow, and are cheap to extract.

But, due to the high weight and high humidity, it is unprofitable to transport the material over long distances, so production is usually arranged near the development site. So, brick factories are always built right on the field.

Certain varieties are found only in some regions. Since the demand for them is high, and factories are often located at a distance from the field, it is necessary to resort to transportation of raw materials.

Clay occurs in the form of lenses or layers, between which sand layers are located. Usually there are about 3-6 layers of clay in a deposit, sometimes up to 20. The thickness of a layer can be either 2-5 or 20-30 m.

Previously, clay was mined mainly on the shores of lakes and rivers. Now it is mined mainly in quarries. Development is usually carried out in an open pit using excavators. Before the start of mining, preparatory work is carried out: geological exploration to determine the type of occurrence and estimate the reserves of raw materials, cleaning the surface from vegetation, removing unusable rocks.

Clay necessarily undergoes natural processing, during which it freezes and matures. After that, using a special technique, the material is machined.

How this happens can be seen in the video below:

Types and varieties of clay

Clay of the most different types, which differ in composition, characteristics and even color. The color of the material depends on the chemical composition. Clay can be white, yellow, red, blue, gray, brown, green and even black.

Clay varieties are distinguished according to various characteristics: plasticity, sinterability, fire resistance, sensitivity to drying, etc.

There are the following types:

bentonite - is used mainly for the purification of vegetable fats, petroleum products, in the process of drilling wells, less often in the production of casting molds;
natural red - contains a lot of iron, high elasticity allows you to use it for working with clay plates or for modeling small sculptures .;
burnt - is characterized by increased durability;
abrasive - used for cleaning polishing metals;
construction - suitable for foundations, blind areas and mortars;
ceramic - used for the manufacture of tableware and decorative items;
powder - convenient for preparing various solutions and mixtures;
refractory - suitable for the production of fireclay bricks;
montmorillonite - used as a bleaching material for cleaning molasses, syrups, beer, wines, fruit juices, vegetable oils, oil products, as an additive to soaps, increasing their quality; also in the production of medicinal pills and agricultural pest control products;
fireclay - it is often used for exterior decoration of buildings. The mixture is prepared by adding water to the powder. To get the desired consistency, it is insisted for three days, stirring occasionally, etc.

Formed by the chemical breakdown of volcanic ash. This clay swells well in water and has a high whitening power compared to other varieties. It can have different colors.

The video details the types of clay and demonstrates their samples:

How much is

The cost of clay can vary significantly depending on its type and characteristics. The price for it ranges from 100 to 500 rubles. for 1 cubic meter m. Sale of clay is quite popular. This is due to the minimum production costs and its rather large reserves in the bowels of the earth.

It is clay, fired at a high temperature (more than 340 degrees) and ground into powder.

Advantages and disadvantages

Nowadays, clay is used in construction mainly as auxiliary material or raw materials for the production of other materials (bricks, ceramics). Materials made from clay have a lot of advantages, and the clay itself can be used for construction and decoration.

The main advantages of clay as a building material can be considered:

complete environmental friendliness;
resistance to high temperatures;
hypoallergenic;
maintaining the humidity level at an optimal level;
free passage of air through walls;
absorption of harmful substances;
waste-free production.

Among the disadvantages of the material should be noted significant shrinkage, deformation of the walls after drying, the need for additional waterproofing of the structure.

Clay is a unique natural material that, regardless of the place of origin, has approximately the same properties and characteristics. The main property of this natural material - hygroscopicity. That is, the clay actively absorbs water, making it more plastic and viscous. Therefore, clay is relatively easy to work with, it can be set to almost any shape, and the firing process will easily eliminate the clay's ability to absorb water, making the product usable.

How to determine the quality of clay

The viscosity of clay depends on its particle size. Fine-grained clay, which is classified as a particularly high-quality raw material, is extremely rare in nature, making such a clay brand very valuable. How to determine the quality of the clay? Usually, when making such an analysis, first of all, they pay attention to the amount of impurities in the material, which affect the strength, refractoriness, color and texture of the final product. However, we do not have a chemical laboratory at our disposal, so there are ways to determine the quality of clay by external signs.

The primary sign that affects the quality of the future pottery is the plasticity of the raw material.... Soft raw materials make it possible to obtain the most diverse and interesting shapes of products, however, this type of clay, despite the complex firing technology, will not have a sufficient margin of safety, and also will not withstand the high firing temperature. Too plastic clay can be "diluted" with coarse-grained materials, which will give it more strength, but this technique is not always desirable, especially when firing products without glaze. To test the plasticity of clay, you can mold something oblong out of it, and then try to break it. If the clay cracks when breaking, the edges remain dry, torn, then this is a sign of non-plastic, non-greasy clay. In turn, if the clay does not tear, but tends to stretch, then this is a sure sign of plasticity. In addition, such clay absorbs water well. Excessive concentration of water in raw materials can lead to the fact that too long pre-drying is required for the product to "mature". Plastic clay is not suitable for products that require a large margin of safety.
All other signs make it possible to identify the quality of the clay only at the final stage, during or after firing the product.

Clay settling is a process that occurs during the firing of clay products.... Plastic clay absorbs more water, which means it also has more sediment. During sedimentation, the clay decreases in size, because it loses bound water from its composition, bringing its concentration to a minimum. During the upsetting process, the most important process also occurs - the binding of glass elements in clay, which turns it into ceramic. This process works best in a non-greasy clay because it requires a high temperature to achieve it, as well as a low concentration of water in the raw material. This means that for the manufacture of high-quality ceramics, it is better to use non-greasy, non-plastic clay. This property can be detected even at the stage of raw material selection.

Clay refractoriness is not a suitable indicator of quality, because it can be determined only at the very last stage, as well as when the product is already damaged. Clay with a melting point of 1200 degrees Celsius is mainly found in nature. That is why the firing process should not be carried out at temperatures above 960 degrees. At this temperature, pores of any material disappear, the process of bonding the glass takes place, which turns the clay into a ceramic product.

It's time to make a short summary. How to determine the quality of clay? The only operation that is required of you when choosing a raw material is to evaluate the plasticity of the clay. To do this, repeat the simplest operation: mold an oblong object out of clay, and then tear it apart, assessing the plasticity. Non-plastic clay is of higher quality because it allows you to get more durable clay products. If a complex shape is required, it is better to turn your attention to plastic clay, which, although it does not withstand very high temperatures, will allow you to get a beautiful souvenir.

Clay is a mineral that has found wide application in various spheres of life. This rather complex rock can be represented by different composition and properties. The conditions for the formation of different types of clays also differ significantly.

What is clay?

Geological science has been studying rock for a long time. Scientists have found that clay, which is not contaminated with foreign impurities, also consists of small particles. The dust diameter does not exceed 0.01 mm. These are particles that belong to a specific group of minerals. It is no coincidence that the use of clay is widespread. Rock is an intricate chemical compound that includes water, silicon, and aluminum.

Clays under the influence of liquid change their properties. Depending on the amount of water that is added to the rock particles, a plastic mass or lime can form. A liquid with added clay has a high degree of viscosity. This property is widely used in construction and renovation applications.

Clay properties

The properties of any rock are completely dependent on the composition. Clay is no exception. The size of the constituent particles also matters. When mixed with, the breed is capable of forming a viscous dough. This property is widely used in various spheres of life. Clay swells in water. This makes it very economical to use. In its raw form, clay dough is able to maintain absolutely any shape. Nothing can be changed after solidification. And so that the product can be preserved for a long time, it is fired. Clay becomes even stronger and stronger when exposed to high temperatures.

If we describe the main properties of clay, one cannot but recall its water resistance. After the rock particles are saturated with the required amount of liquid, it no longer allows moisture to pass through itself. This property is also widely used in construction.

Certain types of clays are capable of refining petroleum products. The same properties of clay are used to refine vegetable fats and oils. Thanks to this, people can consume foods without harmful impurities. Clay absorbs from liquids that can be harmful to health. For the same reason, certain types of rocks are used in cosmetology.

What types of clays are there?

In nature, there are a huge number of types of clay. All of them have found their application in one or another sphere of life. Kaolin is a light-colored clay that is less plastic than other types. It is this breed that is most often used in the paper industry, as well as in the manufacture of tableware.

Refractory clay deserves special attention. It is a white or light gray substance that can withstand temperatures over 1500 degrees during firing. Under the influence of high temperature, refractory clay does not soften and does not lose its useful properties. The rock is widely used in the manufacture of porcelain, as well as in the decoration of premises. Facing tiles made of refractory clay are considered popular.

Molding clays can also be fired at a sufficiently high temperature. They are distinguished by increased plasticity. This refractory clay can be used in metallurgy. With its help, special binding molds for metal casting are made.

In construction, cement clays are most commonly used. These are substances of a grayish hue with an admixture of magnesium. Clay is used for the manufacture of various finishing products, as well as as a connecting link during construction work.

How and where is clay mined?

Clay is a mineral that is not rare today. The substance can be obtained from the ground without any problems. It is easiest to detect the substance in places where rivers used to flow. Clay is considered a product of sedimentary rock and earth's crust. IN industrial scale the extraction of clay is carried out using excavators. The machine cuts off large layers of soil. In this way, much more minerals can be extracted. The problem is that in most cases the clay is layered.

Whole quarries serve as places for the extraction of clay. Work begins with the removal of the topsoil. Most often, clay can be found already at a distance of half a meter from the top. Usually easy to process can be located on the surface itself. In some cases, a mineral can be found under groundwater. In this case, the team installs a special drain to drain the water.

Winter is not a hindrance to mining. To avoid soil freezing, it is insulated with sawdust and other substances with a low level of thermal conductivity. The thickness of the insulation sometimes reaches 50 cm. The already mined clay is also protected from freezing. It is covered with a tarpaulin or other similar material that can maintain the desired temperature until the clay is delivered to the warehouse.

Clay in construction

In the construction industry, clay began to be used from the very first days of its discovery. Today, the material is widely used for the construction of houses in southern regions... Due to the properties of the fossil, the houses are cool in summer and warm and cozy in winter. Only a little sand, clay and straw are taken to make the blocks. After hardening, it turns out to be durable construction materialthat defies any natural factors.

What is the best clay for building houses, experts answer unequivocally. The most suitable is cement clay. Facing tiles are also often made from this material. With the help of such a finish, you can not only decorate the room, but also protect it from fire. After all, cement clay is also refractory.

Clay dishes

Clay cutlery is not only beautiful, but also useful. The material is environmentally friendly. Do not be afraid that the dishes, under the influence of high temperatures, will release substances harmful to health. Many people associate the use of clay with the manufacture of plates, pots and vases. Today, utensils from this material are made on an industrial scale. Everyone can purchase a set made of quality material that can serve for a long time.

Much more appreciated handmade... Whole exhibitions are being organized, where craftsmen can show off their products. You can also purchase high-quality earthenware here. The main thing is that the product is made in a single copy. But the price will be appropriate.

Clay modeling with children

Making various products with clay can be very exciting and fun for a child. Sculpting promotes mental development, improves the motor skills of children's hands. The kid can show imagination for his own pleasure. And what can be done from clay, parents will always tell you.

Clay modeling requires careful preparation. It should be remembered that not all clothes can be removed from the mineral. And the child will definitely put the spots. Therefore, the baby should be changed into working form, and cover the table with oilcloth. What can be done with clay in the first place? First of all, you should sculpt simple oval figures. They can be animals or funny people. With an older child, you will be able to make a plate and a spoon. After hardening, the product can be painted. It will look original and can last for a long time. But it is worth remembering that clay without firing is quite fragile.

The use of clay in medicine

Even in ancient times, people noticed the beneficial properties of clay and began to use them for medicinal purposes. Several types of minerals have anti-inflammatory effects. Due to this, they are used to treat various skin diseases. Clay quickly helps to cope with burns, acne and eczema. But in no case should one engage in self-medication. Separate types clays have different properties. Only a specialist will be able to select the right material and apply it correctly to the sore spot. Without the necessary knowledge and skills, only harm can be done.

Clay is a mineral that is a source of many minerals, vitamins and trace elements. Some types of rock can also be taken internally. Clay is an excellent source of radium. At the same time, the body assimilates that amount of a useful substance that is necessary for normal life.

Clay is able to remove toxins from the blood, as well as normalize metabolism. Due to this, it is often used for various types of poisoning. The powder is taken orally in a small amount with water. But only some types of clay can be used for medicinal purposes.

Clay in cosmetology

Many girls often use cosmetic clay to improve their appearance. The mineral is able to even out skin tone, get rid of acne, and thighs from fat deposits. For cosmetic purposes are used different kinds clay. They all have their own characteristics and properties.

For facial rejuvenation, the most commonly used white mineral is clay. The photos of women who have used this product to improve their faces are impressive. Expression wrinkles are really smoothed out, and age spots disappear completely. For girls with oily skin and large pores, substances are also great - information that can be read on the packaging. But it is still better to use any clay after consulting a beautician.

Applying blue clay

This rock has good anti-inflammatory properties. It contains salts and minerals necessary for normal functioning. Blue clay masks should be done for people who have a tendency to skin rashes. With the help of a natural substance, acne and comedones are perfectly treated.

Blue clay can also lighten skin. 10 procedures will help for a long time get rid of freckles and age spots. In addition, it perfectly smoothes superficial wrinkles.

Green clay

This substance is also widely used in cosmetology. Green clay has excellent absorbent properties. Thanks to this, it is possible to quickly cleanse the body of harmful substances and toxins. The clay can be applied to both the face and the whole body.

Green clay wraps are considered popular. The mineral helps to restore the body's water balance and remove excess moisture. This property helps girls get rid of cellulite, as well as make their skin smoother and smoother.

Red clay

Red clay will be most optimal for people who are prone to allergic reactions. This substance has a special shade due to its copper and iron oxide content. Only the extracted substance cannot be immediately used in cosmetology. Making clay for various masks - laborious process... It is the red clay that prepares with special attention for use. The breed is cleared of various harmful impurities that can harm the skin.

Red clay masks perfectly relieve redness and skin irritation. The material is also widely used in medicine. Red clay promotes faster and postoperative scars less noticeable.

The remarkable properties of natural mineral clays have been known since ancient times. Even then, clay was actively used not only in medicine, but also in cosmetology. Ancient healers made various poultices and rubbing from it. Inside, the clay was taken when its absorbent effect was needed. It helped to get rid of bacteria well and allowed to remove toxins from the body. Clay therapy helped with various poisonings, epidemics and muscle pains. Nowadays clay is no less popular. It is often used in dermatology. Medicinal ointments and pastes are made from it. Clay is also widely used in cosmetology. It is usually found in face masks.

The main property of cosmetic clay is to cleanse and dry the skin. Clay is able to absorb excess sebum and sweat secretions. In addition, it perfectly cleanses the skin of the face, eliminates flaking, irritation and redness. Clay masks in facial care can be used for both oily and dry skin. In addition, clay can enhance the bactericidal effect of certain substances. It is often added to anti-inflammatory ointments and masks. There are different types of cosmetic clays, which we will cover in this article.

Clays differ in color, which depends on their mineral composition. The composition of clays depends on their place of origin. Clay can be white, blue, green, red, yellow and black (gray). Each type of clay has its own specific qualities and is used in medicine and cosmetology for different purposes. You can purchase natural cosmetic clay at pharmacies or cosmetics stores.

White cosmetic clay White clay (Kaolin) looks like a homogeneous white powder with a yellow or grayish tint, or it can be a dense lump. It is greasy to the touch. It dries well, cleanses, and tightens the skin. White clay is able to absorb excess fat, it visibly tightens pores. You need to know that this type of cosmetic clay also has a slight whitening effect. In addition, with its help, a woman can align the oval of the face. White clay is also an excellent antiseptic. It is used in the composition of bactericidal and anti-inflammatory face care products. Regular use of white clay will make your skin velvety and more elastic. The complexion will improve and freshen up. White clay is the most common. It is on its basis that most face masks are made. It is hypoallergenic and suitable for all skin types, even the most sensitive, and with oily skin it normalizes the fat balance. Kaolin is the most delicate abrasive that can be used as a soft scrub. This property of white clay is very valuable for skin with inflammatory acne, for which coarse abrasives are unacceptable, since they can aggravate the course of this skin lesion. It is also used in the form of powders, ointments, pastes, as well as for diaper rash and burns. White clay is an indispensable component in cleansing masks. In addition, do-it-yourself tooth powder or paste with the addition of clay not only whitens teeth even in heavy smokers and "coffee lovers" but also removes tartar, strengthens enamel, and reduces the threat of caries.

The darker the color of the clay, the better it will remove fat and more effectively cope with acne.

Blue cosmetic clay

This clay has anti-inflammatory properties, it contains all the mineral salts and trace elements we need. It is able to prevent the appearance of acne, effectively accelerates the healing of wounds on the skin. This clay is great for cleansing the skin of the face, improves its color. Blue clay is also used to smooth mimic wrinkles. It rejuvenates the skin, making it firmer and more elastic. Blue clay can also lighten freckles and age spots. When used regularly, this type of clay can be great for problematic skin. It disinfects and evens out the skin, relieves acne. It activates blood circulation and speeds up the metabolic process in skin cells. In addition, traditional medicine uses blue clay as a very effective remedy for baldness. And also, blue clay softens and tones the skin, also has anti-cellulite, antibacterial and anti-stress effects. Foot masks based on blue Cambrian clay improved the microcirculation of the skin of the lower extremities, which was expressed by an increase in skin firmness and elasticity, a decrease in edema and the severity of the "feeling of heaviness in the legs." Due to the high adsorption capacity of Cambrian clay, the use of a foot mask in the area of \u200b\u200bthe feet for 20 minutes 1-2 times a week helps to reduce the degree of sweating of the feet, eliminate unpleasant odors and can be used as a prophylactic agent for fungal and bacterial infections of the skin of the feet.

Green cosmetic clay

Green clay has this color thanks to the iron oxide. Taken directly from the quarry, the green clay looks like a dark green wet mass. This clay has found wide application in cosmetology. It can be the basis for cosmetics, and also comes in the form of masks, wraps and compresses. Due to the content of a large amount of trace elements, it helps to restore the skin's hydrobalance and has remarkable absorbing properties. Green clay softens and cleanses the skin. It relieves irritation, has a drying effect. Green clay masks perfectly cleanse the pores of the face, eliminate oily shine. At home, you can mix green clay with another type of clay.

Green clay has excellent absorbent properties. It is ideal for deep cleansing of the skin. Best for oily skin and scalp, used to combat seborrhea. Contributes to the shrinking of pores and improves the function of the sebaceous glands. It has excellent tonic properties. It causes blood flow to the surface of the skin and provides it with the necessary nutrition. Stimulates the regeneration of skin cells. Tightens the skin and restores the face line. Effectively softens, smoothes wrinkles and relieves puffiness. It restores normal metabolism and has antibacterial properties, as it contains a large amount of silver. Green clay baths cleanse and soften the skin, pleasantly relieve the feeling of fatigue, stress and irritation due to the natural ability to take away everything negative energyaccumulated per day.

Red cosmetic clay

Red clay has this color due to the combination of iron oxide and copper. It is best suited for women with sensitive skin prone to allergic reactions. Masks made from this clay relieve irritation and redness on the face. They can also help get rid of flaky and itchy skin. Red clay can also be used for dry, dehydrated skin. It will help aging and sluggish skin. This type of clay improves blood circulation, contributes to a greater saturation of the facial skin with oxygen. It is also used when there is a lack of iron in the body - it is taken orally.

When rubbed into the scalp, red clay strengthens weak and brittle hair, nourishes the hair follicles and treats oily seborrhea. The components of red clay effectively nourish and restore tired skin, help smooth out premature wrinkles, and also have the effect of "nurturing" involuntary facial expressions, especially in the forehead area.

Pink cosmetic clay

Pink clay does not exist in nature, it is the result of mixing white and red clay. This clay is perfect for all skin types. Smoothes small wrinkles, softens the skin, tightens the face contour. Pink clay has a rejuvenating effect. It nourishes and cleanses the skin, making it softer and more elastic. It is also widely used in masks and applications for weakened hair and nails. It has a refreshing and revitalizing effect. Pink clay baths moisturize the skin, relieve fatigue, have a tonic effect and improve metabolic processes in tissues, creating a feeling of freshness and comfort.

Yellow cosmetic clay

Yellow clay contains a lot of potassium and iron, as well as a number of other rare trace elements. It saturates the skin with oxygen. Has a tonic effect. Improves complexion quickly, effectively and permanently. Nourishes hair, scalp, helps to get rid of dandruff. Yellow clay is capable of absorbing waste products of the body and killing pathogenic bacteria. It saturates the skin with oxygen and removes harmful toxins in various inflammatory processes, including acne. Yellow clay is great for aging and tired skin. It smoothes wrinkles, softens and cleanses the skin well, gives it elasticity and freshness. Yellow clay also exfoliates dead skin cells, softening rough skin on the hands, elbows and legs; promotes the healing of small cracks. Due to its high adsorption capacity, yellow clay effectively removes sweating of the feet, eliminates their unpleasant odor. Yellow clay baths relieve fatigue after physical exertion, improve metabolic processes in tissues, improve the condition of the skin, make it smooth and velvety.

Black (gray) cosmetic clay

Black clay contains strontium, quartz, iron, magnesium and calcium. It cleanses the skin very well. This type of clay is able to perfectly absorb all harmful toxins and skin impurities. Contributes to the narrowing of the pores of the face. Suitable for normal, oily and combination skin.

The most active of all types of clays, is mined at sea depths. This is one of the most powerful tools in the eternal female fight against cellulite and body fat. Black clay is used to nourish dehydrated dry skin. It also relaxes tired muscles, relieves rheumatic pains and effectively fights bruises.

Clay belongs to secondary rocks that were formed as a result of weathering of rock massifs during the evolutionary process. Clay is used more often than other materials as a building material. The composition of the clay is very complex and unstable. In its pure form, clay contains practically no impurities. The diameter of its particles does not exceed 0.01 mm, as a rule, clay is plastic. All types of clays contain chemically bound water, it is held in the form of the thinnest films between particles of clay material.

The clay contains silicon and aluminum components. The most common impurities are iron hydroxide, alkaline earth metal oxides quartz and iron sulfide. Rocks with a high alumina content are used to obtain refractory materials; the alumina content in such rocks ranges from 25 to 30%.

When all types of clays get wet, water fills the gaps between the particles, as a result of which they easily move relative to each other. This property determines the plasticity of clay materials.

Clay material is widespread in nature. Clays are divided into subgroups depending on the mineral composition and particle diameter, the presence of certain impurities. There are such types of clay:

red,
white,
sandy,
clay for porcelain,
kaolinic.

The granulometry of certain types of materials depends on the mineral components and chemical composition. Almost all varieties of this unique fossil are characterized by plasticity, adsorption, and swelling. When wet, shrinkage, swelling are characteristic, these properties are decisive when using the material in industry.

Industrial technical requirements the rock is subdivided into varieties:

fusible,
refractory,
adsorptive,
kaolinic.

Damp clay becomes plastic, it is able to take almost any shape.

Plastics are called "greasy" because they feel like a greasy material to the touch. Clay varieties with a low degree of plasticity are called "lean" or lean. Products made from such materials quickly disintegrate; “skinny” clay is not suitable for brick production.

Dried clay keeps the shape well, which was given to it, while it slightly decreases in volume, thickens, hardens and becomes as strong as stone. Due to these properties, clay has long been considered the most widely used material for the manufacture of dishes and other household items.
Among other things, this breed has such an ability as stickiness.
Having absorbed a certain amount of moisture, the material no longer allows water to pass through, this property determines the water resistance of the material.
Another property of clay is hiding power. Due to this property, clay has long been used to cover the walls of buildings and stoves.
The sorption capacity of the material makes it possible to use clay as a purifier for fats and petroleum products.

All of the above properties ensure a long service life for objects made from clay.

Clays and their origins

By origin, clay materials are divided into subgroups.

Sedimentary clays. They are formed as a result of application of destroyed rock layers by water flows. These materials are divided into marine and mainland. According to the name of the first, it is clear that clay is formed on the seabed, in the second case, the formation occurs on the continents, in the bottom sediments of rivers and lakes.

Under natural conditions, this variety has a brown tint, it is given to the material by iron-containing compounds - ferrum oxides, which are contained in clay in an amount of 5 to 9%. These are usually sedimentary clays. They are formed as a result of water application of destroyed rock layers.

During the firing process, the red clay turns red or white, depending on the process conditions and the type of firing equipment. This variety can withstand heating up to 1100 degrees.

This type of clay is plastic, kneads well. The high elasticity of the material determines its use as a material for sculptural modeling.

Natural fossil deposits are found everywhere. They often accumulate in sea or freshwater lagoons. In the case of sea bays, clay is a heterogeneous mass, it has numerous impurities.

When wet, the clay acquires a light gray tint; as a result of the firing process, it turns into a beautiful white material. This type of clay is characterized by elasticity.
Due to the absence of iron compounds, white clay is slightly translucent. It is widely used for the production of household items, tableware, jugs, decorative figurines. In addition, the material is used in the production of tiles and sanitary ware.
Objects made of this clay are covered with glaze and kept in ovens at 900-950 degrees.

Porous mass for the production of ceramics

The raw material is a clay material with a low calcium content and high porosity.

This clay consists of kaolinite, illite and other aluminosilicates, and there are also inclusions of sand and carbonates. Silica and alumina are the basis of clay minerals.
The porous mass belongs to the sedimentary types of clay. It is formed as a result of water application of destroyed rock layers.
The natural color of such clay ranges from white to brown. There are also greenish clays. The material is fired at low temperatures.

Majolica

It is a low-melting type of clay material that contains a large amount of white alumina. The raw material is fired at a low temperature. The majolica is glazed with special mixtures containing tin compounds.

The word "majolica" comes from the name of the island of Mallorca, where this material was first used. Majolica was widely used in Italy. Traditionally, majolica items are called earthenware, because for the first time they began to be produced in special departments for the manufacture of earthenware.

Fireplace clay mass

This rock includes quartz, a significant amount of feldspar and chamotte. These are shelf rocks by origin. They form at a depth of about two hundred meters. A prerequisite is the absence of any kind of currents.

Black material. After firing, the mass resembles ivory products in color. Thanks to the use of glaze, products made from raw materials become unusually durable and have high water resistance.

This raw material is a baked mass. It is fired at a temperature of 1100 - 1300 degrees. The firing process is carried out under close supervision in compliance with technological rulesotherwise the clay products may crumble.

Stone ceramic mass is used for modeling, for the manufacture of various ceramic objects. Products made from this material are very beautiful. Stone ceramics have unique technical properties.

The raw materials include feldspar, a significant amount of quartz and kaolin. This type of clay does not contain iron impurities.

When moistened with water, the mass acquires a gray tint, and after the firing process it becomes perfectly white. The material is fired in furnaces at a temperature of 1300 - 1400 degrees. This raw material is very flexible.

It is not recommended to use this variety for work on pottery circles... The material is very dense, practically without pores, and the absorption of water is very low. The fired material becomes transparent. Items made of porcelain clay are coated with various glazes.

Materials for rough ceramics

Large-porous clay is used for the production of large-sized items, often used in construction. Products of the material are distinguished by high heat resistance, they perfectly withstand temperature fluctuations.

The plastic properties of raw materials depend on the presence of quartz and aluminum in the compound. Characteristics material due to the presence of a significant content of chamotte and alumina.

The material belongs to the refractory varieties. Melting temperature - 1400 1600 degrees. Coarse ceramic material is perfectly sintered, it practically does not shrink. These properties determine its use for the production of dimensional objects, as well as large panels and mosaics.

Montmorillonite Clay

The raw material is used as a bleach for cleaning tent syrups, in brewing, in the production of juice and refined oils. This material improves the quality of finished products, in addition, this type of clay is used as a means to combat rodents and insects.

Adsorption clay

A characteristic feature is high binding properties, a high degree of catalysis. The most common among adsorption clays is bentonite.

Colored clay materials

Multi-colored clay is a material that contains metal oxides or pigments and is a homogeneous mixture.

When pigments penetrate into the thickness of the material, some of them remain in suspension, while the homogeneity of the tone of the raw material is disturbed.
Natural pigments give the clay one shade or another, they are divided into two categories: oxides of metallic elements and the actual dyes.
Oxides are natural components natural originformed in the thickness of the earth's punishment. These substances are subjected to purification and fine grinding. To give the clay a particular color, copper oxide is most often used. This substance acquires a greenish tint during firing as a result of the oxidation process.
To give the material a blue tint, oxygen-containing cobalt compounds are used. Chromium compounds provide the color of olives, while magnesium and nickel compounds provide brown and gray, respectively.
Coloring components are added to raw materials in an amount of 1 to 5%. Higher pigment contents can lead to undesirable effects during the firing process.

Scope of application

Clay is actively used in construction for the manufacture of bricks and ceramics. It has undeniable advantages, as well as a relatively low cost. The advantages of this raw material include thermal stability, adsorption properties, environmental friendliness, and air permeability.