Fluorite

Three colourless Fluorite crystals with perfect cleavage forming an octahedron. Largest crystal: 4.0 cm x 3.3 cm x 3.2 cm. Fluorite (CaF2) has a large range of colours from violet to white and can be colourless. Lustre is vitreous and streak is white. Hardness is 4 and cleavage is perfect in four directions and forms an octahedron. Fluorite is usually found in its cubic form or penetration twins but can also be octahedral, dodecahedral (rare), cleavage masses, granular or columnar. Fluorescent.