Ordoñezite
Ordoñezite or ordóñezite is a rare tetragonal zinc antimonate mineral with chemical formula: ZnSb2O6.
| 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] |
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.
gollark: The deltas thing would introduce quite a lot of complexity in processing, you see.
gollark: But this is also not very space-efficient (although most notes will be small enough that this isn't a massive issue).
gollark: I was thinking about how to do revisions in minoteaur™, you see, and the easiest method would just be to, on every edit, store a compressed version of the content (this is also what dokuwiki does).
gollark: I see.
gollark: Specifically UTF-8 text.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.