Valleriite in the Cubanite-bearing Ores from the Chugoku District

Abstract

Cubanite, which seems to have been crystallized out directly from the ore solution, was discovered in abundance in some pyrometasomatic deposits such as Koyo, Hakki, Mihara and Saezaki mines. Tiny bands of the mineral were also discovered in the meso-hypothermal veins of the Daiei, mine. These Cubanite-bearing ores always contain veinlets or irregular lenticular masses of valleriite and exhibit many interesting exsolution textures among chalcopyrite, cubanite, pyrrhotite, sphalerite and valleriite.
Valleriite occurs commonly in tiny veinlets or irregular lenses about 4 to 170 microns in length and 3 to 10 microns in width, and is often arranged along the crystallographic structure of cubanite and chalcopyrite or along the crystal grains and mineral boundaries.
This paper deals with the paragenetic relations between valleriite and other Cu-Fe-S system minerals.