These are lab created purple-pink to orange-red perovskite. Smaller pieces can be purchased by weight range and larger pieces are labelled with their gram weight and letter in the photo and they can be purchased individually.
This is a very odd and rare laser crystal, yttrium aluminum pervoskite (YAP). It was grown in the 80s in the soviet union for use in lasers, but never caught on as an alternative to its better-known cousin yttrium aluminum garnet (YAG). It has a denser crystal structure, higher hardness and greater brilliance than YAG, and best of all it has a rich orange-red color when cerium is added. This color is also pleochroic, so when cut stones are oriented correctly they can look very similar to imperial topaz, with a more pink-violet center and rich red-orange tips. Overall in my opinion cut stones look even better and more lively than YAG which already cuts exceptional gems.
YAP is an excellent material to facet, easy to cut and polish and with a high hardness of 8.5, an RI of 1.94 and good dispersion which makes for very lively stones even before the color factors in. It is suitable for use in all kinds of jewelry.
