How to distinguish pyrite from Marcasite?

Marcasite is a common mineral, sulfide, one of the polymorphic varieties of natural iron sulfide. Obsolete syn. – “radiant pyrite.” Content (in%): Fe—46,6; S – 53,4; impurities of arsenic, antimony, cobalt, thallium, bismuth, and copper are present in small quantities. Slightly soluble in HCl, and in HNO3 – with great difficulty. In air it tends to decompose (the faster and more intensely, the higher the air humidity) with the formation of iron sulfates and the release of H2SO4, which also quickly decomposes the accompanying sulfides and carbonates. Under conditions of lack of oxygen, native sulfur can also form during the destruction of marcasite.

Main diagnostic signs

• chalcopyrite – lower hardness (3,5-4) and more intense yellow color;
• cobaltine – lower hardness (3,5) and a different crystal shape (like pyrite);
• pyrrhotite – lower hardness (3,5-4,5) and darker color;
• gold – lower hardness (2,5-3) and yellow color of the line.

Crystallizes from slightly acidic solutions under reducing conditions, usually at lower temperatures than pyrite. Formed in hydrothermal deposits along with pyrite, chalcopyrite, galena and other sulfides; often replaces pyrite and pyrrhotite in the oxidation zone of sulfide ores. In sedimentary rocks, it is distributed mainly in the form of nodules in limestones, coal-bearing sandy-clay deposits, shales and marine clays.

Place of Birth

Marcasite is found much less frequently than pyrite and, unlike pyrite, never forms large deposits in the form of continuous ores. It is widely distributed in small quantities in sedimentary rocks in many regions of Russia, for example, coal-bearing deposits of the Moscow Lignite Basin in the Tula Region. and Kuri-Kamenskoye and Troitse-Bainovskoye deposits of clayey deposits east of Yekaterinburg. Of the hydrothermal deposits, the Blavinskoe deposit (Orenburg region, Southern Urals) has the largest amount of marcasite, where it is found in the form of sporadically distributed fine-crystalline aggregates in paragenesis with quartz, pyrite, sphalerite, chalcopyrite, and wurtzite. Well-formed large crystals were found in hydrothermal deposits in Germany (Claustal and Freiberg deposits).

Application

It is used along with pyrite to produce sulfuric acid. Alchemists of the Middle Ages used the term “marcasitae” to designate pyrite and sulfur compounds in general. In France in the 1813th-1814th centuries. Faceted pyrite was sold as inserts in cheap jewelry under the name “marcasite,” but they learned to distinguish between marcasite and pyrite only in the 1813th century. In Prussia, during the Napoleonic Wars of 1813-XNUMX, in return for the jewelry made of precious metals and stones donated to equip the troops, ladies were given iron ones, often signed “Gold gab ich fur Eisen, XNUMX” (“Exchanged gold for iron, XNUMX”). And pyrite inserts, called “marcasite,” due to their bright color and metallic luster, served as a suitable complement to such jewelry, giving them a unique, sophisticated flavor. It caught on, and subsequently the fashion for such jewelry arose in France, from where it spread throughout the world. The material used in jewelry is pyrite, as it would be more correct to call it.

Today, marcasite is also highly valued. One of the museums in Paris houses a mirror made from this unusual material.

Marcasite is a stone for those who do not like monotony. This is all due to the fact that this mineral changes its shade under the influence of light, i.e. Marcasite looks different in different lighting conditions.

It is used very often in the jewelry industry. It is most often framed in silver. With rare exceptions, this stone is combined with gold and other precious metals. The mineral is widely used in the manufacture of pendants, earrings, and rings. Bracelets are not made from marcasite very often due to its fragility.

Marcasite is also used in the manufacture of expensive souvenirs, which can be very different in shape.

Properties of the Mineral

Color	From bronze, brass-yellow (a greenish tint is possible) to almost white when freshly chipped. Marcasite is characterized by a red-yellow-blue tarnish.
Line color	the black
Origin of the name	Arabic or Moorish name, from pyrite and similar pyrites of uncertain origin.
Opening year	known since ancient times
IMA status	valid, first described before 1959 (before IMA)
Chemical formula	FeS 2
Brilliance	metal
Transparency	opaque
Cleavage	average for
Kink	uneven stepped
Hardness	6
Thermal properties	P. tr. on coal it burns with a blue flame, releasing SO2 and turning into red Fe2O3. In recovery flame fuses into a dark magnetic ball in the closed. tr. gives sublimate S and residue FeS
Typical impurities	Cu,As
Strunz (8th edition)	2/D.20-10
Hey’s CIM Ref.	3.9.4
Dana (7th edition)	2.12.2.1
Dana (8th edition)	2.12.2.1
Molecular weight	119.98
Cell Options	a = 4.436Å, b = 5.414Å, c = 3.381Å
Attitude	a:b:c = 0.819 : 1 : 0.624
Number of formula units (Z)	2
Unit cell volume	V 81.20 ų
Twinning	usually along the cockscomb, less often along
Point group	mmm (2/m 2/m 2/m) – Dipyramidal
Space group	Pnnm
Density (calculated)	4.875
Density (measured)	4.887
Pleochroism	сильный
Type	anisotropic
Optical anisotropy	strong, yellow to green
Color in reflected light	creamy white, light yellowish white
Selection form	occurs in the form of tabular, short-columnar, bipyramidal, lance-shaped, needle-shaped crystals. The main simple forms are: (101), (110), (010), (130), (111), (100), etc. comb intergrowths are known that arise as a result of multiple twinning. Aggregates of the mineral are radial, kidney-shaped; powdery (black deposits), pseudomorphoses according to org. remnants
Classes on taxonomy of the USSR	Sulfides
Syngonia	rhombic
fragility	Yes

View the Marcasite mineral in mineral stores

Photo of Mineral

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• Marcasite or radiant pyrite

When struck, marcasite smells of sulfur and emits sparks. You can often see a brownish crust of oxidation and weathering on it.

Many years ago it was used by alchemists. Since the stone is masculine, it gives its owner too much emotional strength, so you need to handle it very carefully so as not to cause trouble.

Marcasite jewelry is known as a fool’s form of white gold. This article provides a simple method for cleaning marcasite jewelry.

Pyrite means “on fire” in ancient Greek, referring to its ability to produce sparks when struck.

Pyrite is a mineral, iron disulfide (FeS2), synonymous with sulfur pyrite, Inca stone. The hardness of pyrite on the Mohs scale is 6-6,5.

Marcasite has the same chemical formula as pyrite – iron disulfide (FeS2), but differs from pyrite in physical and crystallographic properties (the arrangement of atoms in space). Marcasite is less common than pyrite. Another name for marcasite is radiant pyrite. They learned to distinguish between these two natural iron sulfides only in the XNUMXth century. In jewelry, the name “marcasite” is used as a trade name to designate beautiful pyrite inlays in jewelry.

Pyrite with marcasite, Dzheganas Gorge, Karachay-Cherkess Republic, North Caucasus, year of extraction – 2019.

Pyrite, Dzheganas Gorge, Karachay-Cherkess Republic, North Caucasus, year of extraction – 2019.

In a humid environment, pyrite and marcasite crystals are destroyed over time, oxidizing to limonite.

Pyrite often forms pseudomorphs based on organic remains, that is, it repeats the shape of a biological body: wood or various remains of ancient organisms. Sometimes pyrites and marcasites found in the Jeganas Gorge repeat the shape of organisms that lived in the Tethys Ocean about 145 million years ago. During the time of the continent of Gondwana and the ancient ocean of Tethys, a catastrophe of unprecedented scale occurred, which practically destroyed all life on our planet. The ash covered many organisms living in the ocean. Without access to air, belemnites (ancient squids) lay for many millions of years. The calcite rostrum-beak remained, and the soft tissues, which had turned into a lump, were replaced by an iron compound – pyrite.

Pseudomorphosis – pyrite on belemnite (Dzheganas Gorge, Karachay-Cherkess Republic, Northern Caucasus, year of extraction – 2019).

Sometimes pyrite is insultingly called “fool’s gold.” However, in classical gold deposits, gold is often associated with pyrite, both spatially and in the form of microscopic inclusions. In the Roman Empire, free gold was mined from such deposits by grinding the rock and washing away the lighter minerals. But most of the precious metal remained inside the pyrite ore. In modern conditions, such gold can be extracted by chemical extraction. Pyrite turned out to be not such a “fool’s gold”.

Pyrite is a special mineral that contributed to the survival of mankind in the Stone Age (2 million – 6000 years ago). When struck against a hard surface, pyrite produces sparks that burn brighter and longer than flint sparks. Thus, it was possible to light a fire in inclement weather, which greatly facilitated the life of our ancestors in harsh natural conditions. In one of the oldest Vedic texts, the Rig Veda, dating from 1900-1100. BC e., there are numerous references to the production of fire using pyrite.

When pyrite is oxidized in water saturated with oxygen, coloring pigments are obtained – red and yellow ocher. 40000 years ago, ancient man used ocher in cave paintings, as evidenced by finds in Spain, France and Australia. Thus, pyrite participated in the birth of art.

Pyrite is mentioned in ancient Sumerian, Assyrian, Chinese texts, Greek philosophy, and medieval poetry. It was used to make tanning agents in tanneries and a paint fixer for fabrics. Pyrite derivatives were used in medicine as an astringent – for rinsing, washing, lotions, and for disinfecting wounds and premises. This is mentioned in the Ebers Papyrus, an ancient Egyptian medical treatise from 1550 BC. e., the oldest medical manuscript known to us.

In the Middle Ages, pyrite was used to make inserts for decorating buckles, pendants, watch cases and bracelets. Pyrite was cut, like diamonds, in the shape of a rose, which is why it was called Alpine diamond.

In 1896, M. I. Pylyaev, in his book “Precious Stones,” described a ring with pyrite, which was worn by the wife of Emperor Paul I, Empress Maria Fedorovna; she did not take it off from her youth until her death. The book also mentions the exquisite horse harness and saddle of Boris Godunov, decorated with pyrite and stored in the Moscow Armory Chamber.

Mirrors made from pyrite are found throughout pre-Columbian Mesoamerica. Mirrors could be made from one large pyrite crystal, or many small ones, glued to a mosaic-like base. They were known among the Olmecs, Aztecs, Mayans, and Toltecs. The earliest dates back to 2000 BC. Concave mirrors were used to start fires. Pyrite mirrors were worn as decorations on the head, back, tied to a belt, kept on altars, and used in religious ceremonies. They had a sacred meaning – they personified the sun. Royalty, aristocrats and the highest ranks of clergy had the right to wear them. Pyrite mirrors were widely used for fortune telling and predicting the future. In 1547 – 1577, Bernardino de Sahagún, in his manuscript “General History of Things of New Spain,” which is the best pearl of the Renaissance, tells the legend of the last Aztec emperor Montezuma II, who saw the fall of his empire at the hands of the conquistadors while reading fortunes in a pyrite mirror.

Pyrite mirror, 700 – 900 AD, found in the ruins of the ancient pre-Columbian Aztec city of Xochicalco (translated as “city of flowers”, Xochicalco, modern territory – the state of Morelo, Mexico). Kept in the Pitt Rivers Museum, Oxford University.

In the 16th century, Hernán Cortés sent pyrite mirrors as offerings to the Spanish royal court. Such curiosities became objects of desire and collecting among European nobility, scientists and alchemists.

The Incas considered pyrite a stone of health. According to legends, it drove away evil spirits, gave sharpness to vision, allowed one to look into the future and open a portal to the world of the gods.

Magical and talismanic properties of pyrite

• In the Middle Ages, it was believed that pyrite gave courage and strength to people.
• Lithotherapists say that pyrite should be kept on your desk to attract good luck and material wealth.
• Pyrite increases motivation, gives its owner the energy of Mother Nature, saturates the body with health, and normalizes all internal processes.
• Suitable for weakened people or people who have experienced severe stress.
• Helps you believe in your own strength.
• Gives you the opportunity to achieve your goals and achieve your cherished dreams.
• Protects the wearer from all types of negative energy.
• Strengthens the nervous system and helps fight stress.
• Strengthens the body’s immunity, increases overall tone.
• Improves mood.
• Helps attract material wealth.