- align=center bgcolor="#9966FF"	Molybdenite		- align=center	- align=center bgcolor="#9966FF"	General		-	Category	Mineral	-	Chemical formula	molybdenum sulfide:MoS2	- align="center" bgcolor="#9966FF"	Identification		-	Color	Black, lead-silvery gray	-	Crystal habit	Thin, platy hexagonal crystals terminated by pinacoidal faces, also as tapering six-sided pyramids that can be truncated by the pinacoids. Also massive, lamellar and in small grains in sulfide ore bodies.	-	Crystal system	Hexagonal; 6/m 2/m 2/m	-	Cleavage	* Perfect	-	Fracture	flaky	-	Mohs Scale hardness	1 - 1.5	-	Luster	Metallic	-	Refractive index	Opaque	-	Pleochroism	N/A	-	Streak	bluish - gray	-	Specific gravity	4.73	-	Fusibility	Infusible	-	Solubility	?	-	Other Characteristics	Thin cleavage sheets and crystals are flexible, but not elastic. It has a greasy feel and leaves marks on fingers.	- align="center" bgcolor="#9966FF"	Major varieties		-		-

Molybdenite is a mineral of molybdenum disulfide, MoS₂. Similar in appearance and feel to graphite, molybdenite has a lubricating effect that is a consequence of its layered structure. The atomic structure consists of a sheet of molybdenum atoms sandwiched between sheets of sulfide atoms. The Mo-S bonds are strong, but the interaction between the sulfur atoms at the top and bottom of separate sandwich-like tri-layers is weak, resulting in easy slippage as well as cleavage planes.

Associated minerals include pyrite, chalcopyrite, quartz, anhydrite, fluorite, and scheelite. Occurs in high temperature hydrothermal ore deposits. Important deposits include the disseminated porphyry molybdenum deposit at Questa, New Mexico. Molybdenite also occurs in porphry copper deposits of Arizona, Colorado, Utah, and Mexico.

The element rhenium is always present in molybdenite as a substitute for molybdenum usually in the parts per million (ppm) range, but often up to 1-2%. High rhenium content results in a structural variety detectable by X-ray diffraction techniques. Molybdenite ores are essentially the only source for rhenium. The presence of the radioactive isotope rhenium-187 and its daughter isotope osmium-187 provides a useful geochronologic dating technique.

References and external links

---

• Dana's Manual of Mineralogy ISBN 0471032883
• Mineralgalleries.com
• Webmineral
• Mindat.org
• Molybdenite Dating

Sulfide minerals | Molybdenum minerals | Lubricants

Molibdenita | Molybdénite | Molibdenite | Molibdenitas | Molybdeniet | Молибденит | Molybdenit | Molybdeenihohde