What is the mineral molybdenum used for?

Wasserbley (wasserblei) – molybdenite or graphite (Krivovichev V.G., 2008)
Muchuanite (muchuanite) – molybdenite or jordisite; rejected by IMA as a mineral name in its own right
Femolite (femolite) – iron-containing variety of molybdenite

Polymorphism: This chemical composition is dimorphic in nature: in addition to the mineral molybdenite, the amorphous mineral jordisite is also found. Two polytypes are also known: molybdenite-2H (common) and molybdenite-3R (rare).

Systemy: Hexagonal
Composition (formula): MoS₂, possible impurity Re
Color: Lead gray to lead black, often with a faint bluish tint
Trait Color: Lead-gray to bluish-gray, shiny, turns green when rubbed
Transparency: Opaque
Cleavage: Very perfect
Fracture: Uneven
Gloss: Metallic
Hardness: 1-1,5
Density (specific gravity), g/cm3: 4,62-4,73 – measured; 4,998 – estimated
Brittleness: Thin molybdenite leaves are flexible, but not elastic.

Special properties: Oily to the touch. Transparent in infrared light. It has very strong anisotropy and pleochroism (in thin section). Semiconductor, electrical conductivity at room temperature is negligible, but increases with increasing temperature.

When the molybdenite feature is rubbed, it acquires a greenish tint, while the graphite feature remains gray. Galena has a higher specific gravity and hardness, and a cubic crystal shape. Tetradymite has a stronger luster and a higher specific gravity.

Molybdenite crystals have the appearance of hexagonal tables, less often prismatic, the basal faces are covered with streaks. Molybdenite is usually observed in flake- or leaf-shaped aggregates. Sometimes there are spherulite formations, nests, rosettes and earthy varieties.

High-temperature hydrothermal (veins), contact-metamorphic (skarns), found in meteorites

Molybdenite is the only industrial source of molybdenum. Along the way, impurity rhenium is extracted from molybdenite.
Molybdenum is used to alloy steels to produce heat-resistant and corrosion-resistant alloys. Molybdenum tape and wire are needed for the manufacture of high-temperature furnaces and electric current inputs in light bulbs.
Molybdenum compounds are used as catalysts for chemical reactions, components of glazes and dye pigments.
Molybdenum single crystals are used to produce mirrors for high-power gas-dynamic lasers.
Molybdenum is necessary for the manufacture of the cathode of lithium batteries and for the production of thermoelectric generators.
Previously used in radio engineering for the manufacture of detectors.
Molybdenite is used as a dry lubricant, especially at high temperatures, and also as a component of lubricants. However, for lubrication (in particular, in a car), it should be used only in sealed units, otherwise, under the influence of water and atmospheric oxygen, molybdenite turns into abrasive molybdenum oxide.
Molybdenum affects plant reproduction and is used in fertilizing, for example, for berry crops.
Micro amounts of molybdenum are necessary for the normal development of the body. They make the work of antioxidants, including vitamin C, more effective. With a lack of molybdenum, a weakened immune system is observed.
At the same time, dust from molybdenum and its compounds is an allergen that irritates the respiratory tract.

Molybdenite is a mineral, molybdenum sulfide. Chemical composition. Molybdenum (Mo) 60%, sulfur (S) 40%. The crystal structure of molybdenite is a typical layered lattice, where flat networks formed by Mo layers are located between two layers of S ions, parallel to the (0001) plane.

Obsolete synonym: molybdenum shine.

At the break it is not brittle, but flexible and elastic, greasy to the touch (writes on paper). It decomposes in concentrated sulfuric acid with difficulty at low boiling; it dissolves slightly and slowly in HNO3.

Molybdenite is of high-temperature hydrothermal origin, both vein and metasomatic.
It is found in hydrothermal veins and in copper-molybdenum-porphyry deposits. Also present in granites and granite pegmatites. Molybdenite is sometimes found in meteorites.

Main diagnostic signs

Due to its hexagonal shape and low hardness, molybdenite can be confused with graphite. They are distinguished as follows: when the molybdenite line is rubbed, it acquires a greenish color, and the graphite line remains gray. Galena has a higher specific gravity and hardness, and a cubic crystal shape.

Application

Molybdenite is the most important raw material for molybdenum production. Along the way, rhenium and selenium are extracted from molybdenite.

Molybdenum is used to alloy steels to produce heat-resistant and corrosion-resistant alloys. Molybdenum tape and wire are needed for the manufacture of high-temperature furnaces and electric current inputs in light bulbs.

Molybdenum compounds are used as catalysts for chemical reactions, components of glazes and dye pigments.

Molybdenum single crystals are used to produce mirrors for high-power gas-dynamic lasers.
Molybdenum is necessary for the manufacture of the cathode of lithium batteries and for the production of thermoelectric generators.

Previously used in radio engineering for the manufacture of detectors.

In the 11th-13th centuries, Japanese craftsmen used molybdenum in the manufacture of bladed weapons, which allowed them to increase the strength and reduce the fragility of the blade.
Molybdenite is used as a dry lubricant, especially at high temperatures, and also as a component of lubricants. However, for lubrication (in particular, in a car), it should be used only in sealed units, otherwise, under the influence of water and atmospheric oxygen, molybdenite turns into abrasive molybdenum oxide.
Molybdenum affects plant reproduction and is used in fertilizing, for example, for berry crops.
Micro amounts of molybdenum are necessary for the normal development of the body. They make the work of antioxidants, including vitamin C, more effective. With a lack of molybdenum, a weakened immune system is observed.
At the same time, dust from molybdenum and its compounds is an allergen that irritates the respiratory tract.

Place of Birth

Russia: Ilmen Mountains, Southern Urals.

Gutaiskoye deposit, Chikoy river, Transbaikalia.
Bulgaria
Selimitsa Selimitsa, Vitosha, Bulgaria – crystals up to 6-7 cm
Japan
Perhaps some of the finest and clearest molybdenite crystals in the world were found in the Hiras River, Prefecture. Gifu Hirase, Gifu. Well-developed, thick tabular hexagonal crystals up to 15 cm, beveled by the edges of the pyramids, were found in a quartz vein cutting through biotite granite. Loose floaters of molybdenite usually fall out of a highly fractured matrix. Less perfect, incomplete crystals of molybdenite up to 20 cm are kept in the Geological Survey Museum in Tsukuba Tsukuba. Subparallel rosette-shaped aggregates and masses up to 50 cm are also found.
Namibia
Damaraland, Namibia. Plates up to 20 cm – sample of the Ministry of Music named after A.E. Fersman
Madagascar
Deformed crystal 25x18x2 cm (Guillemin, 1972)
Australia
Kingsgate, N.S. Wales-crystals more than 5-6 cm – sample of the Ministry of Music named after A.E. Fersman

Properties of the Mineral

Color	Lead-gray to black, often with a characteristic bluish or pinkish tint. In transmitted light it is pale yellow to red-brown
Line color	Bluish-gray. The gray, crushed line takes on an onion-green color (the graphite line remains gray)
Origin of the name	from the Greek molybdos – lead, because in ancient times molybdenite was not distinguished from galena
Opening year	known since ancient times
IMA status	valid, first described before 1959 (before IMA)
Chemical formula	MoS 2
Brilliance	metal
Transparency	opaque
Cleavage	very perfect in
Kink	the mineral is elastic mica-like
Hardness	1 1,5
Electrical properties of the mineral	Semiconductor
Thermal properties	Does not melt, slightly coloring the flame yellowish-green.
Strunz (8th edition)	2/D.25-10
Hey’s CIM Ref.	3.8.6
Dana (8th edition)	2.12.10.1
Molecular weight	160.07
Cell Options	a = 3.16Å, c = 12.3Å
Attitude	a:c = 1:3,892
Number of formula units (Z)	2
Unit cell volume	V 106.37 Å³
Point group	6/mmm (6/m 2/m 2/m) – Dihexagonal Dipyramidal
Space group	P63/mmc
Density (calculated)	4.998
Density (measured)	4.62 – 4.73
Pleochroism	strongly expressed
Type	anisotropic
Optical anisotropy	very strong
Selection form	Well-formed crystals are common and are represented by hexagonal tablets. The aggregates are dense, finely scaly, leafy, scaly-spherulitic, spherical shiny aggregates.
Classes on taxonomy of the USSR	Sulfides
IMA classes	Sulfides
Syngonia	hexagonal
Literature	Talantsev A.S., Belogub E.V., Grabezhev A.I., Litoshko D.N. Molybdenite // Mineralogy of the Urals. Elements. Carbides. Sulfides. Sverdlovsk 1990. pp. 172-179.