GLAZE MATERIALS are available in different amounts, stated on each individual item. There are price breaks for the more you buy!!
COBALT CARBONATE (45-47 1/2% cobalt by weight) is a very strong coloring oxide used in glazes and stains to produce blues. Disperses well for even color. Combined with magnesium, a purple is possible. A little goes a long way.
Minimum order quantity is 1/4 lb. type .25 (COCO)