Three pieces of widgiemoolthalite displayed at the Harvard Museum of Natural History. The box under the center piece had sides slightly longer than one inch. Placard (not pictured) reads: Widgiemoolthalite Ni 5 (CO 3 ) 4 (OH) 2 ·5H 2 O Agnew Mine, Leinster, Western Australia Australia 140226 — Photo: Collin Knopp-Schwyn · CC BY 4.0
Widgiemoolthalite
A bluish-green hydrated nickel carbonate formed when nickel sulfide weathers — named for Widgiemooltha, Western Australia.
Intro adapted from Wikipedia (CC BY-SA).
Widgiemoolthalite is an IMA-recognized mineral species in the carbonate class, with the chemical formula Ni₅(CO₃)₄(OH)₂·4-5H₂O.
It crystallizes in the monoclinic crystal system.
Key properties: specific gravity 3.13; Pale bluish green streak; Silky luster; optically biaxial.
IMA symbol Wmo, IMA status: approved, named in 1992.
Found in a stockpile of weathered ore from a hydrothermal nickel deposit.
It is found associated with Gaspéite.
The name refers to its occurrence near Widgiemooltha, Western Australia.