These are lab created fancy sapphires grown by the flame fusion method. Each has a special cut and can be purchased individually.
These are some neat lab grown sapphires--we don't usually work with materials grown specifically for gem usage, particularly by the flame fusion, one of our cutters came across some material and really wanted to cut it. These include rich greens colored by cobalt, classic blues, some pink-yellow bicolors and a few cobalt blue spinels. Note the bicolor sapphires are grown with techniques originally developed for making bicolor laser rods.
Cobalt green sapphire in particular is very neat. It can show some of the finest green color of any gem, but it is difficult to grow consistently, with the color varying from more blue to more yellow even within the same crystal and also often exsolving tiny crystals of blue cobalt aluminate. Our friend Arya is working with several PhD researchers to unravel its secrets to grow large, consistent examples without any inclusions.
As is typical of flame fusion blue sapphire these stones have strong color zoning. The green cobalt sapphires show slightly varied colors and a few have blue cobalt aluminate inclusions.
