Scholarlink

Abstract <p>The paper presents original results of studying platinum group minerals (PGM) in graphic galena-chalcopyrite ores of the central part of the Oktyabr’sky Cu–Ni–PGE deposit. Three successive mechanisms of PGM aggregate formation are proposed: growth from melt, subsolidus transformations and metasomatic processes. They can be divided into seven stages: (1) accumulation of a critical amount of PGE and TABSs in the residual (Cu–Pb–sulfide) melt due to fractional crystallization of sulfide melt; (2) crystallization of graphic intergrowths with distillation and concentration of incompatible elements in the form of “drops” along the sulfide–silicate boundary; (3) crystallization of platinum group minerals from this melt: sperrylite, altaite, cabriite-I, paolovite-I, and hessite-bearing solid solution (hessite-ss); (4) growth of maslovite-I crystals on early nucleation grains; (5) completion of melt crystallization with formation of Michenerite, Sobolevskite-bearing solid solution (sobolevskite-ss), froodite-I and Au–Ag alloys; (6) subsolidus transformations with decomposition of sobolevskite-ss—sobolevskite + cabriite-II + paolovite-II; hessite-ss—hessite + maslovite-II, as well as additional growth of froodite-II; and (7) growth of sperrylite metacrystals and formation of Au–Ag alloys. It is confirmed that sulfide melt fractionation plays a dominant role in the formation of large PGM aggregates. A new variety of sobolevskite—Cu-Ni-Sb-sobolevskite is described for the first time.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

The Sequence and Mechanisms of Crystallization of Precious Metal Minerals in Veins of Graphic Galena-Chalcopyrite Ores in the Central Part of the Oktyabr’sky Cu–Ni–PGE Deposit

  • 期刊论文

  • 发表日期：

    2025年8月1日

查看全文
  • I. A. Kuzmin,
  • V. M. Kalugin,
  • V. V. Smolensky

摘要

Abstract

The paper presents original results of studying platinum group minerals (PGM) in graphic galena-chalcopyrite ores of the central part of the Oktyabr’sky Cu–Ni–PGE deposit. Three successive mechanisms of PGM aggregate formation are proposed: growth from melt, subsolidus transformations and metasomatic processes. They can be divided into seven stages: (1) accumulation of a critical amount of PGE and TABSs in the residual (Cu–Pb–sulfide) melt due to fractional crystallization of sulfide melt; (2) crystallization of graphic intergrowths with distillation and concentration of incompatible elements in the form of “drops” along the sulfide–silicate boundary; (3) crystallization of platinum group minerals from this melt: sperrylite, altaite, cabriite-I, paolovite-I, and hessite-bearing solid solution (hessite-ss); (4) growth of maslovite-I crystals on early nucleation grains; (5) completion of melt crystallization with formation of Michenerite, Sobolevskite-bearing solid solution (sobolevskite-ss), froodite-I and Au–Ag alloys; (6) subsolidus transformations with decomposition of sobolevskite-ss—sobolevskite + cabriite-II + paolovite-II; hessite-ss—hessite + maslovite-II, as well as additional growth of froodite-II; and (7) growth of sperrylite metacrystals and formation of Au–Ag alloys. It is confirmed that sulfide melt fractionation plays a dominant role in the formation of large PGM aggregates. A new variety of sobolevskite—Cu-Ni-Sb-sobolevskite is described for the first time.