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www.mineralgallery.co.za Minerals P-T |
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Name
Siderite
Chemistry
FeCO3, Iron Carbonate
Uses
As a mineral specimen and as a minor ore of iron
Color
Color is white, yellow, yellowish brown, brown and reddish brown. Some specimens show an iridescence.
Hardness
3.5 to 4.5
Specific gravity
3.8
Crystals
The crystals are commonly curved rhombohedrons that are sometimes flattened to appear bladed, rarely scalahedral, and massive forms such as botryoidal and earthy are also found
Accompanied by:
It occurs in veins with sulfide ores and with quartz, pyrite and sphalerite in hydrothermal deposits.
Similar to:
Siderite is rarely seen in rock shops because fine crystals are scarce.
Yet it sometimes forms large crystals with tiny attached crystals that, when iridescent, make a wonderful, colorful, satiny, shimmering effect. It belongs to the calcite group of minerals and forms similar rhombohedral crystals.
Luster is vitreous or pearly in some specimens.
Transparency crystals are usually translucent.
Fracture is jagged.
Streak is white.
Other Characteristics: becomes magnetic when heated, effervesces slightly with contact with acid.
Best Field Indicators are crystal habit, slight reaction to acids, cleavage
