A brass-yellow mineral, iron sulfide (FeS2),
found commonly in near-surface deposits. It is found as tabular or prismatic
crystals in the orthorhombic system, as cockscomb aggregates as stalactitic,
globular,a nd radiating forms. It has a metallic luster and is brittle.
Hardness 6–6.5; relative density 4.9.
AND PLANETARY SCIENCE