Ettringite with Black Gaudefroyite

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Yellow Ettringite: Ca6Al2(SO4)3(OH) and rare, Black Gaudefroyite Crystals: Ca4Mn3-x+3(BO3)3(CO3)(O,OH)3 from the N'Chwaning and Wessels mines of the Kalahari Manganese Field in South Africa. Colin R. Owen Collection

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Size: 5079px × 3483px
Location: CRO collection, Somerset West, South Africa
Photo credit: © Andre Joubert / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: calsium, chwaning, ettringite, gaudefroyite, manganese, ore, rare, sturmanite, wessels, yellow