Adamite (Var.: Cuprian Adamite), Ferrilotharmeyerite , Beaverite-(Cu) Locality: Tsumeb Mine (Tsumcorp Mine), Tsumeb , Otjikoto (Oshikoto) Region, Namibia ( Locality at mindat.org ) Size: 3.4 x 2.9 x 1.3 cm. There are numerous gemmy, deep green crystals of cuprian adamite, some doubly terminated to about 1 cm in length! The crystals have inclusions of Ferrilotharmeyerite which lends them color. Sprinkling them are sub-mm sized, but bright yellow beaverite. Ex. Willy Israel Collection. — Photo: Robert M. Lavinsky · CC BY-SA 3.0
Ferrilotharmeyerite
Ferrilotharmeyerite is an IMA-recognized mineral species in the arsenate class, with the chemical formula CaZnFe³⁺(AsO₄)₂(OH)·H₂O.
It crystallizes in the monoclinic crystal system (space group C2/m). It is a member of the Natrochalcite structural group.
Key properties: Mohs hardness 3; specific gravity 4.25; Very pale yellow streak; Adamantine to greasy luster; optically biaxial.
IMA symbol Flmy, IMA status: approved, named in 1986.
Very rare, on museum specimens from a dolostone-hosted hydrothermal polymetallic ore deposit.
It is found associated with Conichalcite, scorodite, schneiderhöhnite, beudantite, tennantite, calcite.
As the ferric iron analog of lotharmeyerite.