Molybdenite is a soft, gray sulfide mineral (MoS2),
the chief ore of molybdenum. It is found
in pegmatites, igneous,
and metamorphic rocks. It has hexagonal
system tabular prisms, flakes, and fine granules and is lead-gray in color
with a metallic luster. Hardness 1–1.5, relative density 4.7.
Image source: Mineralogical Information Institute, courtesy of the
Purified molybdenite has properties very similar to those of graphite,
and is used as a lubricant (see lubrication).
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