Blue cubic zirconia round cabochon in 8mm.
Being a cabochon (often shortened to cab) means it is not faceted, and has a domed front surface and a flat back.
These stones can't be fired with the clay, as they could crack or discolour if exposed to high temperatures, so need to be set in a bezel. Make your own using fine silver bezel wire, or do it the easy way with a bezel cup. Set it into metal clay and fire with the piece, creating a professional setting ready for you to put the stone in once the piece is fired and polished. Fix it in place by pushing the sides of the bezel around the stone with a Bezel Pusher.
Dimensions: 3mm Diameter x approx. 1.5-2mm high