The world of stone is boundless and fabulously interesting. Amethyst and agate, rock crystal and granite, malachite and pebbles on the shore have their own history. Man has been using stone since time immemorial. At first, he served him as an instrument of labor. In the future, the amazing properties that this material possesses contributed to the fact that it began to play a huge role in the development of human culture.
Using a sharp stone, primitive man dissected the carcass of an animal he had killed. From the same material, people made spatulas, scrapers and bowls. Taking flat fragments, they ground the grains, and made jewelry from shiny and colored stones. Somewhat later, the scope of this material expanded. The stone began to be used in architecture and construction, in decorative arts and sculpture, as well as in jewelry.
Today, without this material, a person cannot evencan imagine his life.
Stone and mineral - principles of difference
As a rule, we consider these two words to be synonymous. In principle, a stone can be called a mineral, and vice versa. This will not be a gross mistake. However, these elements still have several significant differences by which they are distinguished and classified.
A mineral is a chemical substance of one kind or another that has a crystalline structure. Sometimes its composition may have slight differences with a similar structure. In such cases, varieties of minerals are distinguished by color or other features.
As for the stone, this concept is broader. It means either a mineral or a hard rock of natural origin.
In order to fully understand the essence of the difference, it is necessary to take into account factors such as:
- The existence of rocks and minerals. In mineralogy, such a classification of stones is considered basic. It is based on the conclusion that minerals are substances with a homogeneous structure. Rocks or just stones in their composition, on the contrary, are heterogeneous.
- Minerals are used in jewelry. Stones, as a rule, are used as a building material.
- Esoteric considers minerals as an object with magical properties. Stones don't have them.
- Minerals are always more expensive. Their cost is sometimes thousands of times higher than the price of stones. Minerals are much less in nature, since in its pure form any substance is much less common than material with impurities. Minerals lookmore beautiful. However, the practical use of rocks or ordinary stones is much greater.
- Minerals are products of nature found directly in the soil. That is why rhinestones, shellby obtained in the laboratory cannot be attributed to this category. You can call them stones.
As a rule, minerals are homogeneous. Impurities present in the composition of the crystal are called inclusions or defects. Because of them, the price of the product is significantly reduced. The mineral, which we call a stone, is best complemented by an adjective. For example, "precious".
Classification of stones
On what grounds are these substances separated? It should be noted that there is no single classification of stones. Jewelers classify them according to one criteria, mineralogists and geologists - according to others, and sellers are primarily interested in the value of the goods they offer.
The first attempt to order the stones was made by professor of mineralogy Kluge Gürich. In 1986, Bauer brought great clarity to this issue. He divided gems into three categories - precious, ornamental, and organic. Rocks were not included in this classification of stones. In turn, these categories are subdivided into orders. However, at present, as a rule, they use the classification of stones proposed by V. Ya. Kievlenko. It distinguishes such groups as:
- Jewelry stones. This category includes the most beautiful and expensive representatives, which, in turn, are divided into 4 orders. The first one contains a ruby and a sapphire,emerald and diamond. The second includes black opal, non-blue sapphire, tadhiite and alexandrite. The third order includes red tourmaline and moonstone, rosolite and topaz, aquamarine and fiery, as well as white opal, spinel and demantoid. The fourth includes citrite and almandine, pyrope and chrysoplase, amethyst and chrysolite, turquoise and beryl, as well as artificial zircon and tourmaline varieties.
- Jewellery and ornamental stones. They are also divided into orders. The first of them contains rock crystal, hematite-bloodstone and rauchtopaz. The second order includes colored chalcedony and agate, rhodonite and amazonite, cahonite and heliotrope, ionizing obsidan and rose quartz, labradorite and common opal, spars and white porite.
- Ornamental stones. Not only jewelry can be made from them. Often they serve as material for various interior items. These include jasper and onyx, ganite and fluorite, obsidan and colored marble.
Sometimes a simplified or everyday classification is used to group stones. She divides them into precious and semi-precious, as well as semi-precious or ornamental.
First grade minerals include: sapphire and diamond, chrysoberyl and ruby, emerald and alexandrite, euclase, spinel and pal. Among precious stones, those that belong to the second grade are also considered. Among them: zircon and opal, almandine and blood amethyst, phenakite and demantoid, red tourmaline and beryl, aquamarine and topaz. If we consider the classification of precious stones by origin, it is worth noting that most of them are minerals. It's homogeneousnatural chemical compounds that have a crystalline structure and a specific composition. The classification of precious stones includes about a hundred types of minerals from an impressive list of 4 thousand elements.
Semi-precious stones include: epidote and garnet, turquoise and diopaz, variegated and green tourmalines, rock crystal (pure water), light amethyst and rauchtopaz, labrador, moonstone and sunstone, as well as chalcedony.
Among the gems are: lapis lazuli and jade, amazonite and bloodstone, varieties of jasper and spar, labradorite, pink and smoky quartz, amber and jet, mother of pearl and corals. When considering the classification of ornamental stones, it becomes clear that their list includes natural volcanic glasses that are part of rocks.
Most of the minerals are formed in the earth. In its depths, this element crystallizes and acquires a stable arrangement of molecules, ions and atoms. Often, minerals have a strict facet shape. The lattice of crystals or their internal structure determines such properties as the type of fracture, density and hardness.
In turn, rocks are a product consisting of several parts fused together. Their structure and characteristics directly depend on the conditions of formation, including the temperature and depth of the rock.
In the classification of natural stones, based on their origin, there are three groups. These are igneous, metamorphic and organic. Let's take a closer look at them.
Magmatic origin
What distinguishes these stones from the rest? ATtranslated from Greek, the word "magma" means "liquid fiery alloy" or "mess". This substance has a temperature reaching up to 1.5 thousand degrees Celsius. When magma cools, minerals and various rocks are formed. If such a process is carried out at a considerable depth, then they are called plutonic, if on the surface of the earth - volcanic.
Magma and lava are different in their viscosity and chemical composition. This also has a direct impact on the further classification of minerals.
It is worth noting that the crystalline structures of the stone begin to form after the cooling of the rocks, when post-magmatic processes occur. Gems begin to "grow" in the voids of rocks, forming sapphires and emeralds, quartz and topaz, alexandrite and ruby. All these minerals are typical representatives of the post-magmatic type.
At low temperatures, which occur near the surface of the earth, the formation of patterned opaque minerals occurs. Among them are agate and opal, chalcedony and malachite.
In the classification of stones and minerals of igneous origin, diamond stands apart. Sometimes he is the same age as the Earth. Diamonds are formed under special conditions. Crystals begin to "grow" in the mantle, at a depth of more than 100 kilometers. The prerequisite for this is the highest temperature and pressure. Diamonds are "delivered" to the surface of the earth by the so-called kimberlite pipes.
Minerals and rocks can also be of sedimentary origin. This is another rather lengthy process of their formation. Its basisis the external influence of water and atmosphere. Under the influence of rivers and precipitation, rock is transported from the surface of the earth. In this case, the rock is washed out and weathered.
Metamorphic origin
Let's consider the second group from the classification of stones. Translated from the Greek language, the word "metamorphosis" means "transformation" or "complete change." Physico-chemical conditions that develop in the bowels of the earth, in particular pressure, temperature and gases, have a significant impact on the deep layers of the soil. Under the influence of various factors, the breeds completely change. This process is also influenced by magma and catalytic substances.
Scientists have identified certain types of metamorphism. Among them:
- Dive. A similar process occurs due to an increase in pressure, as well as the circulation of water solutions.
- Heating.
- Hydration. During this process, rocks interact with aqueous solutions.
- Impact metamorphism caused by explosions and meteor impacts.
- Dislocation metamorphism due to tectonic shifts.
Stones of this type of origin are marble and garnet, feldspar and quartzite.
Organic
Stones from this category are characterized by the fact that many thousands of years ago they were particles of wildlife, and then "froze".
This characteristic underlies the classification of ornamental stones according to their origin. For example:
- ammolite is part of the fossilone of the shell layers;
- Jet is a type of black (hard) coal formed from particles of ancient plants;
- pearls are formed in the shell in the form of mother-of-pearl layers that cover foreign bodies that have fallen into the mollusk;
- coral is a tree-like formation with a calcareous structure found in warm seas;
- amber is the fossilized resin of trees that grew over 40 million years ago;
- Damn's finger - shells of ancient cephalopods, belemnites, that existed 165 million years ago.
Minerals used for jewelry
Classification of jewelry stones can be quite diverse. These minerals are distinguished by value, by belonging to a particular group, etc. But one of the most important classifications of jewelry stones is their breakdown into types based on the appearance of these minerals in the world. This question is very relevant when buying jewelry with an elegant insert. After all, acquiring a valuable and beautiful thing, each buyer would like to understand what is the origin of the mineral. This will allow you to determine how justified the costs incurred.
All gemstones are divided into four types according to their origin. Among them:
- natural;
- imitation of natural;
- synthetic;
- ennobled.
Let's consider in more detail the types listed above, included in the classification of stones used in jewelry, according to theirorigin.
Natural
These minerals are formed in the bowels of the earth by themselves. Man only mines and processes such stones. Jewelers finish these minerals by cutting and polishing them.
The degree of processing for natural stones is very important. When a certain threshold is overcome, the mineral passes from the category of natural to ennobled.
Imitation of natural stones
Such materials are very often used to create jewelry at a lower cost. Buying jewelry with inserts made of imitation of natural stones is preferred by those people for whom it is very important to impress others. The very fact of the non-natural origin of the stone does not bother them.
What materials are used to simulate? For this purpose, natural or artificial stones are used, which, in their external characteristics, are similar to the original. For example, turquoise is often replaced with pressed chips of natural origin. Sometimes colored plastic is used to imitate this mineral. For gems, glass of the corresponding tone is most often taken. Of course, the imitation is easily distinguishable from the original in terms of its structure, chemical composition, and physical properties.
Synthetic stones
The pinnacle of jewelry science is an artificially grown mineral. This is a substance that is wholly or partly man-made. A similar type of origin is mentioned in the case of consideration of minerals includedinto the classification of semi-precious stones, as well as precious ones.
Applicable synthesis technologies have reached such perfection that the physical and chemical properties of natural minerals and their analogues absolutely coincide. Synthetic stone is not always possible to distinguish from natural. On the one hand, this is his big plus. However, for some buyers, the "soul" of a real mineral is important, in certain properties of which many people believe.
Refined stones
These are minerals whose properties have been greatly altered through various processes. For example, at present, jewelers sometimes heat stones. This allows you to change their color. Sometimes minerals are treated with ultraviolet rays. The simplest example of ennobled stones is a diamond, in which a crack is filled with a special compound.
Knowing the classification of jewelry stones and the characteristics of the properties that correspond to a particular group, you can easily determine the value of minerals. Of course, due to their uniqueness and rarity, the most expensive are natural, which have not been subjected to any human impact. Synthesized stones follow them in value. Due to the significant costs of their production, they also have a high cost. But at the same time, in some cases, they win when compared with low-quality natural stone.
Mass of minerals
There is a classification of precious and semi-precious stones and their weight. What is its measurement? For gemstones, the unit of mass iscarat. It is equal to 1.5 grams. Sometimes such a unit is called the "metric carat".
Natural pearls are measured in grains. This is a quarter of a carat. Japanese jewelers sometimes use the momme unit of mass.
The smallest diamond samples are measured using a point. If the jewelry raw material is unprocessed, then its weight is indicated in grams. The same unit is used when weighing ornamental and semi-precious stones. European jewelers sometimes indicate the weight of such minerals in ounces.
Based on the classification of stones by size, their value is determined. However, most often this applies only to precious and semi-precious stones. The cost of a particular gem depends on its mass by only a third. The main component of the price for semi-precious stones is the quality of the mineral, its transparency, color, as well as the skill of the cutter.
Kidney stones
Stones can occur not only in earthly soil. Not all of them are the fruit of human creation. In medical practice, a special type of disease associated with the formation of s alt stones is distinguished. The presence of stones in the kidneys is indicated by back pain and colic, hematuria and pyuria. When diagnosing pathology, it is necessary to determine the type of formations. This will allow you to prescribe the most effective treatment.
What is the classification of kidney stones? These neoplasms are distinguished by the following:
- quantity (as a rule, doctors detectsingle stones);
- localization - in the kidney, bladder or ureter;
- location in the kidney - bilateral or unilateral;
- shape - round, studded, flat with edges or coral;
- size - ranging from the eye of a needle to the volume of a whole kidney.
Based on their origin in the classification of coral stones, formations formed by an organic substance, as well as on an inorganic basis, are distinguished.
According to their chemical composition, kidney stones are:
- oxalate, arising from an excess of oxalic acid s alts in the body;
- phosphate, the development of which is promoted by calcium s alts;
- urate, formed with an increased level of uric acid s alts;
- carbonate, originating from s alts of carbonic acid;
- struvite, formed with an excess of ammonium phosphate.
Calculi of organic origin are separated separately. These are protein, cystine, cholesterol and xanthine stones.
