SYNTHESIS OF PARAMELACONITE - CU4O3

Evidence for the natural occurrence and synthetic preparation of coppe r oxides other than CuO and Cu2O is reviewed. The unequivocal synthesi s of CU4O3 (paramelaconite) is reported for the first time, It is achi eved by extraction of copper or its oxides with concentrated aqueous a mmonia in a Soxhlet apparatus, Quantitative X-ray diffraction analysis of one preparation showed that it consisted of 35% Cu4O3, 27% Cu2O, a nd 38% CuO for a gross composition CuO0.77. (C) 1996 Academic Press, I nc.