Fluorite is usually found in a very pure state, is typically transparent, but can be greenish, yellowish. bluish, red, brown or white colored. It can be found with limestone deposits, dolomite and granite. It is a fairly commonly occurring mineral. It is used widely in the manufacture of steel, glass, enamel wares, chemicals (hydroflouric acid, and is used in many metallurgical processes. It's crystal structure is hexoctahedral. It has a SG of 3 - 3.2 and a hardness of 4. Another unusual property of fluorite is that it is strongly fluorescent and phosphorescent when heated or exposed to electrical discharge. The specimin in the photo came from the Ontario Province of Canada.