|
Gaspeite, a very rare nickel carbonate mineral, with the formula (Ni,Fe,Mg)CO3, is named for the place it was first described, in the Gaspé Peninsula, Québec, Canada. Gaspeite is the nickel rich member of the calcite group. A solid solution series exists between all members of this group with divalent cations readily exchanged within the common crystal structure. It forms massive to reniform pappillary aggregates in fractures, bottryoidal concretions in laterite or fracture infill. It is also present as stains and patinas on iron oxide boxworks of gossanous material. == Paragenesis == Gaspeite is formed in the regolith as a supergene enrichment mineral of hypogene nickel sulfide minerals, generally in arid or semi-arid environments which produce conditions amenable to concentration of calcareous or carbonate minerals in the weathering profile. Gaspeite from Widgiemooltha is associated with talc carbonated komatiite-associated nickel sulfide gossans and is probably formed by substitution of nickel into carbonates such as magnesite which are formed by oxidation of the talc-carbonate lithology, and of primary and supergene nickel sulfide minerals. Gaspeite is formed from a similar process to the weathering of other sulfide minerals to form carbonate minerals. The sulfide minerals which are weathered to produce gaspeite are pentlandite, violarite, millerite and rarely nickeline. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Gaspeite」の詳細全文を読む スポンサード リンク
|