Bromyrite or bromargyrite[4] is a natural mineral form of silver bromide[4] found mainly in Mexico and Chile. Hardness is 1.5 to 2. Related are chlorargyrite and iodyrite.
| Bromargyrite | |
|---|---|
 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 | 2+1⁄2 |
| 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] |
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- ^ a b Mindat page for bromargyrite
- ^ Webmineral page for bromargyrite
- ^ a b Handbook of Mineralogy
- ^ a b "Definition of BROMYRITE". www.merriam-webster.com. Retrieved 2023-01-20.
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