Astrobleme Golden Rain

Authors:
p. 15-24
Keywords:
  • астроблема
  • плазма
  • растворимость
  • аномалии
  • тугоплавкие минералы
  • платиноиды
  • тороидальное золото
  • маггемит
  • рудные поля
Abstract:
The Popigai astrobleme is surrounded by a halo of stable maghemite with iridium and other platinoids, gold, thorium, and REE. Its genesis is associated with the plasma release of ocher dust. There are also placers of toroidal (eolian) gold, often with significant admixtures of Pd, Ir, Ni, and inclusions of not typical for it corundum, spinel, and hematite. Refractory platinum minerals and teardrop-shaped thorianite occurred with gold. It is assumed that the toroidal shape of the gold grains results from the precipitation of noble metals during the plasma cooling.