Ore minerals of the lwami kuroko deposits, Shimane Prefecture, have been investigated. The deposits are composed of network and disseminated type deposits , bedded deposits and gypsum deposits. Ore samples collected from the dump are highly silicified and fractured, and are regarded to have derived from the network and disseminated type deposits.
In addition to sphalerite, galena, pyrite, chalcopyrite, tetrahedrite, luzonite and bornite, which were reported so far, tennantite, enargite, covellite , electrum, sylvanite, petzite and hessite have been confirmed. EPMA analyses of ore minerals revealed that the minerals, not only tetrahedrite, tennantite and sphalerite but also others, are more or less variable in compositlon.
Mineralization sequence in the network and disseminated deposits may be speculated as follows ; quartz with fine grained pyrite→sphalerite and galena with small amounts of chalcopyrite, tetrahedrite, electrum and Au-Ag-Te minerals→pyrite and chalcopyrite with small amounts of bornite covellite , tennantite, luzonite and calcite→luzonite , covellite , calcite and siderite.