Rod-shaped placer gold from downstream of the Yamagano (Nagano) mine, Kagoshima prefecture, Japan

Abstract

Rod-shape placer gold was found in heavy mineral concentrate from downstream of Yamagano mine. The results of SEM-EDX analysis and micro area X-ray diffraction correspond with Ag₃Hg-Au₃Hg phase (= luanheite-weishanite). However, there is possibility that a part of the crystal corresponds with Au₄Hg phase. It is considered that the material was formed by reaching between native gold and artificial liquid mercury. Then, the material is not mineral, however, must also be a nature produced material.