These are pieces of pulled titanium sapphire, an unusual variety of sapphire grown for use in lasers with a padparascha-like orange-pink color (also called Ti:Sapphire or just Ti:Sapph). The stones are each labelled with their letter and weight and can be purchased individually.
This is a very unusual variety of sapphire, colored solely by titanium. This is never found in nature or even in cheap flame fusion sapphire because it requires extreme chemical purity--even a hint of iron mixed in will result in a deep blue color. When it is made just right, however, the result is a bright, sort of padparascha-like pink color which shifts between a starburst pink and a more pink-orange depending on the lighting. We were able to get some leftover offcuts from a laser crystal grower--these were not produced for the gem trade but they make for incredible gems.
The color of these pieces varies because the rind has a darker slightly orange-red color which fades into a Starburst-pink color in the center. This gives a nice range of options. Some stones have a thin black rind which will need to be ground off, but it is very thin and tends to have the richest color right beneath it.
