CaF2 is the chemical formula. Only recently seen used in jewelry. Hardness is 4.
Four directional cleavage. Density is 3.18. Refractive Index is 1.432. Optical character
is isotropic. Fluorite is a very attractive stones ususally for collectors but lately
used is jewelry. Fluorite come in a "alexandrite" variety which displays a color
change effect.