Heterolite ( ) - a mineral of the class of oxides , a family of spinels , is named after the Greek α½²ΟΞ΅ΟΞΏΟ (eteros) - satellite. Synonyms - getaerolite, getairit, heterite, zinc-hausmanite.
| Heterolite | |
|---|---|
| Formula | ZnMn 2 O 4 |
| Molecular mass | 239.26 |
| Opening year | 1877 |
| IMA Status | Valid |
| IMA systematics ( Mills et al., 2009 ) | |
| Class | Oxides and Hydroxides |
| Subclass | Complex oxides |
| Family | Spinels |
| Group | Gausmanita |
| Physical properties | |
| Colour | The black |
| Trait color | Dark brown |
| Shine | Semi-metal |
| Transparency | Opaque |
| Hardness | 6 |
| Microhardness | 757 - 985 kg / mm2 |
| Fragility | Fragile |
| Kink | Uneven |
| Crystallographic properties | |
| Point group | 4 / mmm |
| Space group | I4 / amd |
| Syngonia | Tetragonal syngony |
| Cell options | a = 0.572 nm, c = 0.924 nm |
| Axis ratio | a: c = 1: 1.615 |
| Number of formula units (Z) | four |
| Optical properties | |
| Optical type | Single axis |
| Pleochroism | Weak |
| Internal reflexes | Reddish brown |
Content
Mineral Properties
Crystal structure and morphology
Tetragonal syngony . Space Group - . Cell parameters: a 0 = 0.572 nm ; c 0 = 0.924 nm ; a 0 : c 0 Isostructural with hausmanite . Point group - . The crystals are pseudo-octahedral. Fives with a double plane were observed.
Oriented intergrowths of heterolith with franklinite are known.
Physical properties and physico-chemical constants
The break is uneven. Fragile. Hardness 6. Microhardness 757β985 kg / mm 2 at a load of 50 g. Specific gravity 4.85β5.18. The color is black. The dash is dark brown. The gloss is semi-metallic. Transparent in very thin chips. When electrodialysis does not change.
Heat of formation (-) 315.27 kcal / mol ; isobaric formation potentials at 300 Β° K (-) 289.56 kcal / mol , at 500 K Β° (-) 272.41 kcal / mol , at 900 Β° K (-) 238.56 kcal / mol .
Microscopic characteristic
In transmitted light - dark reddish brown; pleochroism is weak. Double reflection is noticeable. Distinctly anisotropic ; in immersion, anisotropy is poorly noticeable due to reddish-brown internal reflexes.
Chemical Properties
Theoretical composition: ZnO - 34.02%; Mn 2 O 3 - 65.98%. In small amounts, Mn 2+ replaces Zn .
In polished thin sections etched with concentrated HNO 3 , concentrated HCl , SnCl 2 ; from H 2 O 2 boils; a fast acting mixture of H 2 SO 4 + H 2 O 2 . It gives a ZnO coating on coal during soda reduction. Before the soldering tube does not melt.
Finding
Rare hydrothermal mineral. They are found in the form of kidney-shaped crusts with a radial-columnar structure, continuous discharge, small crystals. In Sterling Hill ( New Jersey , USA ), met with franklinite in the form of drusen with chalcophanitis in continuous secretions. In Franklin ( New Jersey , USA ), it was found in association with jeffersonite , gojkinsonite , willemite and calcite in veins that cut massive manganese ore.
Artificial Reception
Obtained by the fusion of sulfates Mn , Zn and Na .
Differences
It differs from similar gausmanite in lower reflectivity and more abundant internal reflexes.
Literature
Chukhrov F.V .. Bonstedt-Kupletskaya. E.M. Minerals. Directory. Issue 3. Complex oxides, titanates, niobates, tantalates, antimonates, hydroxides. - Moscow: Nauka, 1967 .-- S. 95β97. - 676 ββp.