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Genesis and properties of chromite deposits in Denizli region (Southwestern Anatolia), Turkey
Published in Adam Piestrzyński, Mineral Deposits at the Beginning of the 21st Century, 2001
Chromite orebodies contain chromite, heazlewoodite, awaruite, millerite, spinel and/or magnetite. gangue minerals are serpentinized olivine, pyroxene (enstatite), trmolite, Cr-tremolite, clinochlore, pennin, serpentine and calcite. Under the microscope, chromite grains are subhedral or anhedral with diameters varying from 0.5 to 3 mm. Grains are densly fractured. Chrome spinel and magnetite are developed as rims on grains and occur in fractures. The fractures are filled by serpentine minerals. Relict olivine grains are seen rarely in serpentine. In some samples the serpentine minerals are colored by limonite and tiny hematite grains. Awaruite, millerite and heazlewoodite were observed within fractures in serpentine and/or in chlorite. The diameter of these minerals varies from 1 to 8 micrometers. Tremolite was observed in small amounts in some samples only.
Advanced Review on Extraction of Nickel from Primary and Secondary Sources
Published in Mineral Processing and Extractive Metallurgy Review, 2019
Pratima Meshram, Banshi Dhar Pandey
Yüce et al. (2007) observed widespread chromite mineralization in the nickel sulfide ore of the Marmara district of Turkey. Some amounts of magnetite and chromite exist in the ore together with sulfide and oxide type nickel minerals. The ore sample contains 1.32% Ni, 10.79% SiO2, 78.39% Fe2O3, 1.3 g/t Ag, and 1.0 g/t Au. The ore sample is constituted of about 70% magnetite, 15% sulfide minerals, and 5% chromite and iron oxides, as well as 10% gangue minerals. Nickel mineralization in the ore such as pentlandite, violarite, millerite awaruite and asbolane was determined. Due to the complex structure of mineralization, a combination of gravity separation and flotation methods was applied for the concentration of nickel sulfide and oxide ores. A nickel concentrate containing 12.32% Ni was produced with 89.7% recovery and final tailings with 0.088% Ni can be disposed with 4.9% of metal loss.
Muonionalustaite, Ni3(OH)4Cl2·4H2O, a new mineral formed by terrestrial weathering of the Muonionalusta iron (IVA) meteorite, Pajala, Norrbotten, Sweden
Published in GFF, 2021
Dan Holtstam, Luca Bindi, Andreas Karlsson, Johan Söderhielm, Anders Zetterqvist
It is well documented that the Muonionalusta meteorites are associated with crusts of “rust” of varying thickness (Wickman 1964). The terrestrial modification of Muonionalusta has, however, only been superficially investigated to date (Holtstam & Söderhielm 2004; Gurdziel 2012). Verified alteration products are goethite, lepidocrocite, maghemite, magnetite, akaganeite, trevorite, awaruite and nickel (nativus).