Iridescent Pyrite on Calcite from Kazakhstan TF2230 double terminated There is also a "sidecar"

There is also a "sidecar" crystal that is growing off the back and has an interesting self-healed termination that looks as though it is lifting off of the main crystal (see last photo)

pink opal is unique in that it lacks the flashy play-of-color that's often associated with traditional opals

a microcrystalline form of quartz

There is a pronounced twist on this gwindel

Locality: Mexico

Iridescent Pyrite on Calcite from Kazakhstan TF2230 double terminated There is also a "sidecar"Iridescent Pyrite on Calcite from Kazakhstan Approx. Dimensions: 3. 5x3x2 inches Approx. Weight: 195 grams Locality: Sokolovskoe Iron Mine, Kostanay Province, Kazakhstan This is a unique specimen we acquired out of a very small parcel of specimens from a gentleman that collected them in Kazakhstan. It features very brightly colored iridescent pyrite coating fluorescent calcite.