Bromargyrite

From Wikipedia, the free encyclopedia
Jump to: navigation, search
Bromargyrite
Bromargyrit mit gediegen Silber - San Onofre, Mexiko.jpg
Bromargyrite with Silver - San Onofre, Mexico.
General
Category Halide minerals
Formula
(repeating unit)
AgBr
Strunz classification 3.AA.15
Crystal system Isometric
Crystal class Hexoctahedral (m3m)
H-M symbol (4/m 3 2/m)
Space group Fm3m
Unit cell a = 5.7745 Å; Z = 4
Identification
Color Yellowish, greenish brown, bright green
Cleavage None observed
Fracture Irregular/uneven, sub-conchoidal
Tenacity Sectile
Mohs scale hardness
Luster Adamantine, resinous, waxy
Streak White to yellowish white
Diaphaneity Transparent, translucent
Specific gravity 6.474
Optical properties Isotropic
Refractive index n = 2.253
Birefringence δ = 0.000
References [1][2][3]

Bromyrite or bromargyrite is a natural mineral form of silver bromide found mainly in Mexico and Chile. Hardness is 1.5 to 2. Related are chlorargyrite and iodyrite.

It was first described in 1859 for an occurrence in Plateros, Zacatecas, Mexico where it occurred in a silver deposit as an oxidation product of primary ore minerals.[1] It occurs in arid environments along with native silver, iodargyrite and smithsonite along with iron and manganese oxide minerals.[3]

References[edit]