#im in love w nickeline
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taking some notes for my own study later
Nickeline: NiAs, hexagonal, pale copper red
Maucherite: Ni11As8, tetragonal, warm silverly white turning darker grey when oxidised
Gersdorffite: NiAsS, isometric, grey to white
Parkerite: Ni3(Bi,Pb)2S2, monoclinic, pale bronze
Hauchecornite: Ni9BiSbS8, tetragonal, bronzy yellow
Matildite: AgBiS2, trigonal, silvery black or grey
Ni-Co-Ag deposits or five-element (Ni-Co-As-Ag-Bi) vein type deposits, the name is not really that accurate as it often has Fe, U, but we persist. It tends be exist in continental crust where extensional tectonics occur.
Ore precipitation theories
Natural Fracking - This is the current leading theory. Liberation of hydrocarbons during the break up of rocks near hydrothermal systems. Mixing of hydrocarbonates and metal rich hydrothermal fluids precipitate ore (Markl, Burisch, Neumann, 2016).
Iron oxidation - Correlates pyrite abundance with mineralisation (Ondrus, et al., 2003)
Fluid mixing - Fluids of different pH mixing. Ore fluids are shown to be alkaline, and the proposed precipitation is caused by decreasing pH. (Staude, et al., 2012)
Boiling... or Cooling? - High temperatures in the crust mobilise saline and ~400°C fluids, and scavenge Ni-Co-Ag from surrounding rock. The deposition mechanism is reduction and boiling. (Kissin, 1992)
im tired, back to porphyry work. i may or may not come back with more <3
Nickeline (pink/peach) and Maucherite (pinkish grey) with a rim of Gersdorffite (bluish grey) overgrown by intergrown Parkerite (light grey, twinning) and Hauchecornite (dull pink), then overgrown by Matildite (darker grey, rough texture).
Locality: Easter-Duffy Deposit, East Arm Region, Greater Slave Lake, NWT, Canada
Reflected Plane Polarized Light, 200X Magnification
Quick laundry list of minerals most people will have never heard of!
#geology#rocks#mineralogy#im in love w nickeline#peach#!!!!!#five element vein type#note taking w cat :>
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