Pyrite
Color brass yellow; Cubic Crystals, Hardness 6-6.5. Known as "fool's gold", because of its gold-like color, although its specific gravity is much less (gold =18). Present in iron ore.
Hardness 3.5-4, Cleavage in six directions; Specific Gravity 4; Color typically dark-green to purple. Mineral found in zinc ores.
Color red- dark brown- black; Specific gravity 5.26; Hardness 5.5-6.5; not metallic. Present in iron ore.
Cleavage in three perpendicular directions; Specific gravity 7.5; Color lead-gray; Luster metallic. Present in lead ores, used for fishing weights, etc.
Typically black color, though it can oxidize to a red or brown; Hardness 5.5-6.5. Like hematite, forms a common iron ore, and can be difficult to distinguish from hematite but for its diagnostic attraction to magnets.
Typically green-yellow color; Hardness 3.5-4. While the mineral includes iron in its formula, this the most important copper mineral and is very important in copper ores.
Technically this is not a mineral, as there is no uniform atomic structure. This is a natural rust that forms in rocks that contain iron minerals such as hematite, magnetite or pyrite.
Return to Physical Geology Syllabus
Sphalerite 
Hematite 
Galena 
Magnetite 
Chalcopyrite 
Limonite
Return to Kevin McCartney's homepage