Thermal studies on the chalcopyrite-sphalerite intergrowths from pyrrhotite deposit in Japan

Under the ore-microscope, we can find the emulsion texture of chalcopyrite in sphalerite from pyrrhotite deposits in the southwestern district of Japan, and sometimes it appears in the fine beautiful lattice. These textures are interpreted as due to exsolution of a solid solution. Writer has made thermal studies on these sphalerite from Motoyama. Otani, and Futaba mine, and obtained the results as follows: (1) Chalcopyrite emulsion or lamallae in sphalerite from these mines, disappears at 750 ?? 800°C for 24 hours, irrespectively of their types of the deposits or their occurences. (2) ' By heating for 48 hours, chalcopyrite tend to diffuse into sphalerite at 600 ?? 6500°C. (3) Chalcopyrite-sphalerite solution obtained by heating at 800°C for 18 hours, shores the unmixing phenomena by reheating at 700°C for 8 hours.