|Red Iron Oxide||5.00|
Specific gravity: 1.43. A smooth and slightly fat matte surface. This glaze contains both magnesium oxide, which yields pastels, as well as barium oxide, which can make vivid colors. Adding cobalt carbonate in increments from 0.25–2% yields pale to strong lavenders, and adding 1% copper carbonate produces a bright turquoise. The surface becomes extremely dry and grainy with additions of 4% titanium dioxide and above.
Original recipe shared by Milt Friedly in the November 1991 issue of Ceramics Monthly. Not for functional ware.