Stibiconite

Stibiconite is an antimony oxide mineral with formula: Sb₃O₆(OH). Its name originates from Greek "stibi" (antimony) and "konis" (powder), alluding to its composition and habit.^[1][2][3] It is a member of the pyrochlore super group.

Stibiconite
Stibiconite. Locality: Catorce (Real de Catorce), Municipio de Catorce, San Luis Potosí, Mexico (Locality at mindat.org)
General
Category	Oxide minerals
Formula (repeating unit)	Sb3+Sb5+2O6(OH)
Strunz classification	4.DH.20
Crystal system	Isometric
Crystal class	Hexoctahedral (m3m) H-M symbol: (4/m 3 2/m)
Space group	Fd3m
Unit cell	a = 10.27 Å; Z = 8
Identification
Formula mass	478.25 g/mol
Color	Pale yellow to yellowish white, reddish white, orange; gray, brown, black when impure
Crystal habit	Massive, botryoidal, as incrustations, powdery
Cleavage	None
Fracture	Clay-like
Mohs scale hardness	4-5
Luster	Vitreous - dull
Streak	light yellow
Diaphaneity	Transparent to translucent
Specific gravity	4.1 - 5.8, Average = 4.94
Optical properties	Isotropic
Refractive index	n=1.6-1.97
References	[1][2][3]

Discovery and occurrenceEdit

It was first described in 1862 for an occurrence in the Brandholz - Goldkronach District, Fichtelgebirge, Franconia, Bavaria.^[2]

It occurs as a secondary alteration product of other hydrothermal antimony minerals such as stibnite. It occurs in association with cervantite, valentinite, kermesite, native antimony and stibnite. 

This article uses material from the Wikipedia article  Metasyntactic variable, which is released under the  Creative Commons Attribution-ShareAlike 3.0 Unported License.