Arseniosiderite , Boothite Locality: Copper Basin District, Lander County , Nevada , USA ( Locality at mindat.org ) Size: small cabinet, 8.8 x 6.1 x 4.3 cm Boothite with Arseniosiderite According to MINDAT, "This mineral, fully hydrated copper sulphate, is very rare." This is a large specimen smothered in crystallized boothite, composed of stacks and sprays of agglomerated microcrystals. Acquired by John White in 1969. Ex. John White Collection. — Photo: Robert M. Lavinsky · CC BY-SA 3.0
Boothite
A very rare copper sulfate heptahydrate first found near Oakland, California.
Intro adapted from Wikipedia (CC BY-SA).
Boothite is an IMA-recognized mineral species in the sulfate class, with the chemical formula Cu(SO₄)·7H₂O.
It crystallizes in the monoclinic crystal system (space group P2_1/c). It is a member of the Melanterite structural group.
Key properties: Mohs hardness 2–2.5; specific gravity 1.94; Vitreous, silky or pearly if fibrous luster; optically biaxial.
IMA symbol Boo, grandfathered status — known before the IMA’s founding, named in 1903.
An alteration product of chalcopyrite (Alma mine, California, USA).
It is found associated with Chalcanthite, melanterite, pisanite (Alma mine, California, USA).
The mineral was named to honor Professor Edward Booth (1857–1917), American chemist, University of California, Berkeley, California, USA.