Hardness 3 Density 2.7 Color usually colorless, but nuances in blue, yellow, green, red, violet, even black and opaque. Streak White to grayish. Luster Vitreous to pearly or dull. Occurance Calcite is the main ingredience of limestone rocks. It is also the mineral that builds up stalagmites in caves.
Calcite is also a common mineral in hytdrothermal veins.
Notes Reacts violently with hydrochloric acid. Clear calcite is called Iceland spar, since it was mined there. Often flourescent, especially when contaminated by manganeese. A very common mineral Aln n . Sala silver mine , V stmanland.