Faceted Yb:YAG Gemstones, Light Blue Fantasy Cut Laser Garnets

These are faceted light blue ytterbium YAG, a type of blue laser garnet.  The color varies from light greyish-blue to more saturated blue-green.

Yb:YAG is an uncommon type of YAG, grown for use in some infrared lasers including ones used for high power engraving.  While it is used in a variety of infrared laser systems it is surprisingly hard to actually get as industrial scrap--this is because the material is usually annealed immediately after growth, which makes it suitable for use in lasers but also removes the color.

YAG has a high hardness (8.5), a solid RI (1.83), and good dispersion.  It is ideal for use in all kinds of jewelry.