Rare and valuable minerals

Why is pyrite called cat s gold?

PYRITE – mineral, iron sulfide. It is the most common sulfide mineral in the earth’s crust. For its beautiful appearance, noble shade and metallic luster, pyrite is often called “fool’s gold”, and for its ability to produce a spark when struck – “fire stone”. English name: Pyrite Other names (synonyms): Sulfur pyrite, iron pyrite, alpine diamond, alpine diamond, iron liver ore, gold blende, fool’s gold, health stone, Inca stone, cat’s gold, vitriol pyrite, mundic Isolated and described for the first time: The mineral pyrite has been known since ancient times, long before the formal publication of its description. Probably, then, different minerals fell under the “stone that strikes fire.” Medieval alchemists called pyrite marcasite. They learned to distinguish iron sulfide minerals only in the 19th century: pyrrhotite was described in 1835, marcasite in 1845, troilite in 1862 Origin of the name: Pyrite was named in ancient times from the Greek “pyr” – “fire”, because when it hits metal or stone, sparks appear. Described by the ancient Greek naturalist Dioscorides (~50 AD) under the name “περι υληζ ιατρικηζ”, which included both pyrite and chalcopyrite. New items with Pyrite in the product catalog Products containing Pyrite are presented in the following categories:

  • Unique exhibits and interior items,
  • Stones and minerals,
  • Decorations,
  • Products and souvenirs,
  • Fossils,
  • Beads made of stones,
  • Stones in esotericism
  • class Sulfides, Sulfosols
    • subclass Metal sulfides
      • Pirita group
        • mineral Pyrite
          • Bravoite variety
          • variety Spectropyrite

          Bravoite is a variety of pyrite enriched in nickel. Gengleinite is a cobalt-containing bravoite.
          Melnikovite is a fine-grained or amorphous iron sulfide that arises from an iron sulfide gel and usually recrystallizes into pyrite and/or marcasite, sometimes into an aggregate of alternating these two minerals.
          If there is a significant amount of any impurity in the mineral, varieties of pyrite are distinguished by the name of this impurity, for example, gold-bearing pyrite, arsenic-bearing pyrite, lead-bearing pyrite, etc.

          Isomorphism: Pyrite usually contains minor amounts of nickel and forms an isomorphic solid solution series with vaesite (NiS2). Also, pyrite usually contains a small amount of cobalt and forms an isomorphic series with katierite (CoS2).

          Polymorphism: Pyrite, having a cubic system, is a polymorphic analogue of orthorhombic marcasite.
          Syngony: Cubic
          Composition (formula): FeS2

          Color: Golden yellow, straw yellow, brass yellow. The oxidized surface of pyrite is brownish, often tarnished or covered with a thin film of limonite.

          Trait Color: Black, Greenish Black, Brownish Black
          Transparency: Opaque
          Cleavage: Imperfect
          Fracture: Uneven, conchoidal
          Gloss: Metallic
          Hardness: 6-6,5
          Density (specific gravity), g/cm3: 4,8-5
          Brittleness: Brittle

          Special properties: Pyrite is slightly soluble in nitric acid and insoluble in hydrochloric acid. Non-fluorescent. An iridescent tarnish is often observed on the surface of pyrite.
          In a humid environment, pyrite can begin to slowly oxidize due to the development of various bacteria in it. Well-crystallized samples are more stable, and pyrite in the form of sedimentary nodules is subject to faster decomposition.

          In aggregates and in nonspecific crystal forms, pyrite is externally indistinguishable from marcasite. For example, in radial aggregates or black sooty masses. Often nodules offered to collectors as marcasite are pyrite or mixed (with marcasite tending to the outer layer). Marcasite often forms elongated crystals, in contrast to the cubic crystals of pyrite. Marcasite sometimes has a greenish tint. Chalcopyrite, compared to pyrite, has lower hardness (3,5-4), a more intense brass-yellow color, sometimes with a variegated tarnish. Cobaltine has a lower hardness (3,5) and does not have the yellow color of pyrite. Pyrrhotite is also less hard (3,5-4,5) and has a darker color. Gold has a very low hardness (2,5-3), has malleability and a yellow color, which is not typical for pyrite.

          The mineral pyrite forms cubic, pentagon-dodecahedral, and less commonly octahedral crystals. Sometimes there is rough shading on the edges of pyrite crystals. Crystal intergrowths are characteristic. Sometimes it forms doubles.
          Most often, pyrite occurs in the form of continuous granular aggregates, dense confluent masses, radial aggregates, spherulites, kidney-shaped and disc-shaped formations. Pyrite concretions, various nodules, and nodules are typical for sedimentary rocks. Forms thin veins and impregnations. There are pseudomorphs of pyrite based on organic remains (wood, fossil mollusk shells, etc.). Pyrite is often replaced by limonite (during the oxidation of Fe2+ in pyrite it turns into Fe3+ and limonite develops).

          Pyrite is a typical mineral of hydrothermal veins. Widely distributed in sedimentary rocks, found as an accessory mineral. Forms large deposits in the form of nodules on the bottom of sea basins. Pyrite can also be of metasomatic, less often igneous, origin.

          Today, the mineral pyrite was the main raw material for the production of sulfuric acid, sulfur and ferrous sulfate, but recently the processing of pyrite has been economically unprofitable and is rarely used. Waste from pyrite processing is one of the main sources of selenium.
          In some deposits, impurities of gold, silver, copper, nickel and cobalt and other elements are extracted from pyrite.
          A number of patents have been registered for the use of pyrite in the preparation of mastics, expanded clay, cements, concretes, and asphalt concretes; and also as part of the charge during shaft smelting.
          Today, pyrite is widely used as a collection mineral and ornamental stone.

          Do you think that pyrite harmonizes all processes in the body, both on the physical and mental levels. Traditional healers recommend carrying pyrite or jewelry made from it with you. It normalizes all internal processes, is able to influence the nervous system, and helps with nervous exhaustion. Pyrite is called the stone of health.
          The ancient treatises of Pliny the Elder indicate that dry crushed pyrite was used “to treat goiters and ulcers,” which is why it was called a stone of health.
          Pyrite affects the Manipur chakra.

          Pyrite is a powerful magical tool. In the Middle Ages it was often used by alchemists, and now it is used by practicing magicians.
          Pyrite gives great emotional strength, can improve mood, raise overall tone and increase performance. This stone helps to gain self-confidence, get rid of fear, and become a leader.
          In the Middle Ages, pyrite was considered a masculine stone.
          Indoors, it is recommended to place a golden pyrite crystal on the money sector. It will help activate it.

          Interesting Facts

          Because of its yellow metallic color, pyrite was often mistaken for gold, hence its common name “fool’s gold.” Pyrite is easily distinguished from gold in that it is much lighter, but harder than gold (it cannot be scratched with a knife).

          In the Middle Ages, pyrite was the most popular material for conducting alchemical experiments – scientists of that time were firmly convinced that pyrite was the very “philosopher’s stone”, which, according to legend, is capable of giving its owner wealth, happiness and eternal life.

          Pyrite (FeS2) is a mineral that belongs to the class of sulfides, a group of pyrites and marcasites. It is considered one of the most commonly found minerals in the earth’s crust. This class of mineral is the most common representative of these minerals. The percentage composition is as follows: Fe – 46,6%, S – 53,4%, along with inclusions: cobalt, nickel, copper, gold, silicon.

          Because of its external resemblance to gold, it received the nickname “fool’s gold”, “lion’s gold”, “cat’s gold”.

          History

          The origin of the name of the mineral “pyrite” has Greek roots. Translated into Russian, this word means: “stone that produces fire.” The ability of sulfur pyrite to produce sparks when struck was noticed by ancient tribes of people and was used to make fire. The color of pyrite (bronze-yellow hue) resembles gold. This feature of sulfide caused multiple deaths among the tribes inhabiting America during the time of the conquistadors. Ancient conquerors forcibly took away a natural compound in the form of pyrite products, mistaking it for real gold. At the beginning of the 20th century, humanity actively used the semiconductor feature and magnetic properties of this fossil. Currently, the mineral pyrite is used for the production of sulfuric acid, and the ability of this sulfide to restore gold dissolved in solutions has also been used.

          During the Middle Ages, pyrite was known as the “Alpine diamond.” Rich people valued him. Even in those days, jewelers worked with it, offering it as jewelry in combination with watches, bracelets, and buckles. There was still a downside: if even small drops of water got on them, the stone changed color to dark, subsequently turning into limonite. In other words, the effect of corrosion of the product appeared.
          Researchers have repeatedly noticed that in sedimentary rocks of mountains, pyrite can replace fragments of plants and animal bodies. Such fossils can take on a wide variety of forms.

          At different times, adherents of magic used this stone for fortune telling and rituals of religious significance. They also made and still make amulets and talismans from it. In order to sell products with pyrite, today they often counterfeit it, while predicting the duration of operation and the preservation of specified visual characteristics. To obtain such artificial stone, different methods are used. The most relevant are those based on the reaction of acid H2S with iron-containing compounds in a gaseous state or in aqueous, often alkaline solutions, but the reduction of sulfates and other substances with organic components and sulfur can also be used.

          physical properties

          Color Bronze-yellow, yellow tint of brass, gold with a predominance of yellow, sometimes with tarnish.
          Line color Greenish black
          Brilliance Metal
          Transparency Opaque
          Hardness Mohs scale 6 to 6,5 (decreases with increased nickel inclusion)
          Cleavage Very imperfect by (001)
          Kink Crustaceous
          Density 5,01 g / cm³
          Syngonia cubic

          Chemical properties

          Chemical formula FeS2
          Chemical composition Iron (Fe) – 46,6%; Sulfur (S) – 53,4%
          Molar mass 119,975 g / mol
          Oxidation state Fe (+2), S (-1)

          The composition may also contain other elements: Co, Ni, AS, Sb, Cu, Ag, Au.

          In layers located in the upper part of the earth’s crust, under conditions of access to air, pyrite becomes unstable, subject to chemical weathering and oxidation, which subsequently leads to the appearance of “Iron hats” or brown iron ores.

          Crystal structure

          NaCl type structure. The iron atoms form a face-centered cubic lattice (corresponding to the sodium atoms in the NaCl structure). Twin sulfur atoms take the place of chlorine atoms, also forming a face-centered cubic lattice, but shifted by a0/2 relative to the cationic lattice. The axes of twin sulfur atoms are oriented along non-intersecting diagonals of the cubic spatial lattice. The distance between the sulfur atoms connected in each pair by a covalent bond is 2,05 A

          Varieties found in nature

          In nature, pyrite can occur independently in the form of crystals. They will have distinct shading on all sides. In this case, the orientation is strictly perpendicular to the faces. Crystals can be solid or in the form of inclusions in the rock. Associations with sulfides of other types are also found.

          Pyrite is known today in its two subspecies: marcasite and bravoite. Marcasite has a polymorphic form; bravoite has a high nickel content (almost a fifth). If we compare the structure of the crystal lattice and chemical composition, then both options are 100% similar.

          Application

          Chemical Industry

          In the chemical industry, pyrite is an important raw material necessary for the production of sulfuric acid. Its cinders are in demand, like iron ore. If there are impurities such as copper, silver, nickel or gold, they can also be recovered. With its help, it is possible to precipitate gold from solutions containing it, as well as from sea water.

          Metallurgical industry

          If there is a need to purify gaseous vapors from the presence of chlorine, pyrite can also be used for this.

          Jewelcrafting

          This stone requires careful handling. Therefore, jewelers do not use cutting on it, preferring to mount it in special inserts, while maintaining its natural shape. If cutting is carried out, then, as a rule, the result is a rose or cabochon shape. Places where pyrite is used: rings, earrings, bracelets, buttons.

          Agriculture

          Pyrite is a mineral that is useful as a fertilizer additive.

          Other areas

          If there is a disc-shaped stone with radial fibers, then collectors will appreciate them. Rarely, pyrite is still used for this purpose today in the production of sulfuric acid, iron sulfate, and sulfur. Modern technologies involve the use of minerals as a corrective component for cements.

          Place of Birth

          It is not uncommon for large quantities of pyrite (mineral mining) to be discovered during the development of deposits of zinc, copper, and other non-ferrous metals. Since processing is not economically profitable, it is not recovered, but sent to dumps.

          Pyrite deposits in Russia

          • Astafievskoye field
          • Polevskie placers
          • Berezovskoye field
          • Shabrovskoye field

          Enrichment

          The main method for enriching pyrite stone is flotation. If pyrite-polymetallic ore is taken, then at the first stage the removal of non-ferrous metals from the total mass of minerals is carried out. In this case, depression of pyrite is observed with a minimum content of alkali cyanide. After this step, pyrite flotation occurs. Also, such ores can be extracted into a collective concentrate with further division, but in the event that the acidity of the media does not exceed 11. Sphalerite-pyrite concentrates are also divided, but as a result of mixing the pulp in a lime solution and in the presence of aeration with activated carbon . Flotation of sphalerite followed by pyrite from zinc cycle tailings is also acceptable. Sulfuric acid is required to activate pyrite. The presence of sodium silicofluoride and carbon dioxide, including that coming from smoke exhaust units of metallurgical plants, is also important.

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