Ordoñezite

Ordóñezite
General
Category Antimonate mineral
Formula
(repeating unit)
ZnSb2O6
Strunz classification 4.DB.10
Crystal system Tetragonal
Crystal class Ditetragonal dipyramidal (4/mmm)
H-M symbol: (4/m 2/m 2/m)
Space group P42/mnm
Unit cell a = 4.66 Å, c = 9.26 Å; Z = 2
Identification
Color Very light to very dark brown, colorless to pearl-gray, light yellowish olive to dark olive
Crystal habit Pyramidal crystals in drusy or stalactitic masses
Twinning Common on {013}
Fracture Conchoidal
Mohs scale hardness 6.5
Luster Adamantine
Diaphaneity Semitransparent
Specific gravity 6.635
Optical properties Uniaxial (+)
Refractive index N(calculated) = 2.02 - 2.04
References [1][2][3][4]

Ordoñezite or ordóñezite is a rare tetragonal zinc antimonate mineral with chemical formula: ZnSb2O6.

Discovery

Ordóñezite was first discovered and documented by Ezequiel Ordóñez (1867-1950), a Mexican geologist, formerly director of the Geological Institute of Mexico. It was first described in 1953 for an occurrence with cassiterite in veins in rhyolite in the Santín mine which is located about eight kilometres from Santa Catarina, Guanajuato, Mexico.[2] Another locality is El Antimonio, 27 km (17 mi) southwest of Agua Prieta, Sonora, Mexico.[3]

Properties

Optical properties include: semitransparent, very light to very dark colorless to pearl-gray, light yellowish olive to dark olive.

References


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