Efremovite: Difference between revisions
Content deleted Content added
Chris.urs-o (talk | contribs) m wikilink |
m Broken links |
||
| Line 50: | Line 50: | ||
'''Efremovite''' is a rare [[ammonium]] [[sulfate mineral]] with the chemical formula: (NH<sub>4</sub>)<sub>2</sub>Mg<sub>2</sub>(SO<sub>4</sub>)<sub>3</sub>. It is a white to gray [[Cubic crystal system|cubic]] mineral.<ref name=HBM>[http://rruff.geo.arizona.edu/doclib/hom/efremovite.pdf Handbook of Mineralogy]</ref> This anhydrous sulfate occurs as constituent in [[sulfate crust]]s of burning [[coal]] dumps. It is [[hygroscopic]] and when exposed to humid air it slowly converts to the [[hydrate]] form, [[boussingaultite]].<ref>Chesnokov B. V. and Shcherbakova E. P. 1991: Mineralogiya gorelykh otvalov Chelyabinskogo ugolnogo basseina - opyt mineralogii tekhnogenesa. Nauka, Moscow</ref><ref>Jambor J. L. and Grew E. S. 1991: New mineral names. American Mineralogist, 76, pp. 299-305</ref> |
'''Efremovite''' is a rare [[ammonium]] [[sulfate mineral]] with the chemical formula: (NH<sub>4</sub>)<sub>2</sub>Mg<sub>2</sub>(SO<sub>4</sub>)<sub>3</sub>. It is a white to gray [[Cubic crystal system|cubic]] mineral.<ref name=HBM>[http://rruff.geo.arizona.edu/doclib/hom/efremovite.pdf Handbook of Mineralogy]</ref> This anhydrous sulfate occurs as constituent in [[sulfate crust]]s of burning [[coal]] dumps. It is [[hygroscopic]] and when exposed to humid air it slowly converts to the [[hydrate]] form, [[boussingaultite]].<ref>Chesnokov B. V. and Shcherbakova E. P. 1991: Mineralogiya gorelykh otvalov Chelyabinskogo ugolnogo basseina - opyt mineralogii tekhnogenesa. Nauka, Moscow</ref><ref>Jambor J. L. and Grew E. S. 1991: New mineral names. American Mineralogist, 76, pp. 299-305</ref> |
||
It was first described in 1989 for an occurrence in the Chelyabinsk coal basin, Southern [[Urals]], [[Russia]]. It was named for Russian geologist [[Ivan Antonovich Yefremov]] (1907–1972). It has also been reported from several coal mining areas across Europe.<ref name=Mindat/> It occurs in association with [[native sulfur]], |
It was first described in 1989 for an occurrence in the Chelyabinsk coal basin, Southern [[Urals]], [[Russia]]. It was named for Russian geologist [[Ivan Yefremov|Ivan Antonovich Yefremov]] (1907–1972). It has also been reported from several coal mining areas across Europe.<ref name=Mindat/> It occurs in association with [[native sulfur]], {{Interlanguage link|it|kladnoite}}, [[mascagnite]], and [[boussingaultite]].<ref name=HBM/> |
||
==References== |
==References== |
||
Revision as of 10:04, 7 August 2015
| Efremovite | |
|---|---|
| General | |
| Category | Sulfate minerals |
| Formula (repeating unit) | (NH4)2Mg2(SO4)3 |
| Strunz classification | 07.AC.10 |
| Crystal system | Cubic |
| Space group | Isometric tetartoidal H-M Symbol (23) |
| Unit cell | a = 9.99 Å; Z = 2 |
| Identification | |
| Color | White to gray |
| Crystal habit | Equant grains and crusts |
| Cleavage | None |
| Fracture | Uneven |
| Mohs scale hardness | 2 |
| Luster | Vitreous |
| Diaphaneity | Transparent to nearly opaque |
| Specific gravity | 2.52 (calculated) |
| Optical properties | Isotropic |
| Refractive index | n = 1.550 |
| Alters to | Readily hygroscopic |
| References | [1][2][3] |
Efremovite is a rare ammonium sulfate mineral with the chemical formula: (NH4)2Mg2(SO4)3. It is a white to gray cubic mineral.[3] This anhydrous sulfate occurs as constituent in sulfate crusts of burning coal dumps. It is hygroscopic and when exposed to humid air it slowly converts to the hydrate form, boussingaultite.[4][5]
It was first described in 1989 for an occurrence in the Chelyabinsk coal basin, Southern Urals, Russia. It was named for Russian geologist Ivan Antonovich Yefremov (1907–1972). It has also been reported from several coal mining areas across Europe.[2] It occurs in association with native sulfur, it, mascagnite, and boussingaultite.[3]
References
- ^ Efremovite, Webmineral.com
- ^ a b Efremovite, Mindat.org
- ^ a b c Handbook of Mineralogy
- ^ Chesnokov B. V. and Shcherbakova E. P. 1991: Mineralogiya gorelykh otvalov Chelyabinskogo ugolnogo basseina - opyt mineralogii tekhnogenesa. Nauka, Moscow
- ^ Jambor J. L. and Grew E. S. 1991: New mineral names. American Mineralogist, 76, pp. 299-305