Mineral composition and qualitative characteristics of apodolomitic nephrite: case study of body 1 at Prozrachny prospect of the Kavoktinsk deposit, Middle Vitim Highland

Abstract

The results of the mineralogical study of apodolomitic nephrite from the Kavoktinsk deposit are reported. A nephrite formation model (the evolving of diopside after dolomite, the replacement of diopside by tremolite and the replacement of prismatic tremolite by felted-structured tremolite) is presented. Tremolite is occasionally derived directly from dolomite. Tremolite is then replaced by chlorite. Granites provide heat for metasomatism. The involvement of amphibolites in nephrite formation is responsible for a variety of nephrite colours. Metamorphism is responsible for tectonic crushing, which contributes to fluid penetration, and stress, which provides felted nephrite structure.