Molybdenite

Molybdenite (known by the mineral symbol Mol)Mindat.org is a mineral form of molybdenum disulfide. It is similar to the texture of graphite. It sometimes has a slippery effect because of its structure, which is made of sheets of molybdenum and sulfur. It usually has a hexagonal shape, or has a trigonal shape.Handbook of Mineralogy 

It occurs usually with minerals such as quartz or pyrite, and can be found in deposits across mines in the western US, notably New Mexico, Colorado, Utah, and Arizona. It can also be found in Mexico. Sometimes, Rhenium can be found in this mineral. It is very similar to graphite that it can be almost impossible in tell them apart.

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Category:Molybdenum minerals
Category:Sulfide minerals