Calcine and grind.

Blue Stains.—

I.—Oxide of cobalt2 1/2 parts
Oxide of zinc7 1/2 parts
Stone7 1/2 parts
Fire this very hard.
II.—Zinc6 pounds
Flint4 pounds
China clay4 pounds
Oxide of cobalt5 ounces
Hard fire.
III.—Whiting3 3/4 parts
Flint3 3/4 parts
Oxide of cobalt2 1/2 parts

Glost fire.

Turquoise Stain.—

Prepared cobalt1 1/2 parts
Oxide of zinc6 parts
China clay6 parts
Carbonate of soda.1 part

Hard fire.

Materials:

Tin Ash.—
Old lead4 parts
Grain tin2 parts