Fluorite

Sample of colourless, with slight violet tints, of euhedral penetration twins of Fluorite embedded into colourless/yellow subhedral cubic Fluorite. Largest yellow Fluorite crystal size: 2.3 cm x 1.9 cm x 1.5 cm. Largest colourless Fluorite crystal size: 1.0 cm x 1.0 cm x 0.9 cm. Fluorite (CaF2) can be violet, blue, green, yellow, brown, bluish black, pink, rose-red, white or colourless. Lustre is vitreous and streak is white. Hardness is 4 and cleavage is perfect in four directions forming an octahedron. Fluorite usually occurs as cubic or penetration twins but can also be octahedral, dodecahedral, cleavage masses, granular or columnar.