The Suran fluorite-sellatite lode deposits are hosted by Lower Riphean sedimentary rocks (approx 1.5 Ga). Based on field observations and REE analyses, three mineralization stages are distinguishable. The first stage is a redeposition of disseminated fluorite from the dolomitic host rocks by low-temperature and high-saline fluids into the Suran fault zone. Two types of fluorite and, in tectonic contact with diabase, sellaite (MgF_2) were formed. The second stage fluorite with high REE contents and a significant negative Eu anomaly is related to tectonic activation of the fault system during Cadomian or Uralian (Late Paleozoic) events. These fluids (>250 deg) probably originated from Mid-Riphean rhyolitic rocks. Optical spar formed on late cross veins by remobilisation of all older types of mineralization.
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