COPPER OXIDE BLACK

Description

This colourant tends to produce greens of a grayish nature when used in lead glazes, turquoise in alkalis, yellow-greens in potash and blue-greens in barium base glazes.  Lead glazes with copper content should not be used on utility ware because the copper tends to increase the solubility of the lead.

Copper carbonate can be substituted for copper oxide if the amount is doubled.