Copper oxide. Specification: CuO(%)>98. Insoluble substance in hydrochloric acid(%)<0.2 . Insoluble substance in water(%)<0.1. Chloride(%)<0.2 Sulfate(%)<0.2 Fineness is 1.3um. Property:Brown black powder,density: 6.3-6.49g/cm3,melting point:1326癈,soluble in diluted acid, NH4Cl.(NH4)2CO3, potassium cyanide solution,insoluble in water and alcohol, slowly soluble in ammonia. Application:The green,red and blue dyeing of glass, ceramic, porcelain enamel; produce dyes, catalyzer and other oxides, desulfurizer of oil, the preparation of synthetic cut stone and other copper oxides. Also suitable for artificial silk industry. Packaging:25kg metal pail.