Sabinaite
| Sabinaite | |
|---|---|
 |
|
| General and classification | |
| other names |
IMA 1978-071 |
| chemical formula | Na 4 Zr 2 Ti [O | CO 3 ] 4 |
|
Mineral class (and possibly department) |
Carbonates and nitrates (formerly carbonates, nitrates and borates) |
|
System no. to Strunz and to Dana |
5.BB.20 ( 8th edition : V / C.05) 16a.05.04.01 |
| Crystallographic Data | |
| Crystal system | monoclinic |
| Crystal class ; symbol | monoclinic prismatic; 2 / m |
| Room group (no.) | C 2 / c (No. 15) |
| Lattice parameters |
a = 10.20 Å ; b = 6.62 Å; c = 17.96 Å β = 94.1 ° |
| Formula units | Z = 4 |
| Frequent crystal faces | {001}, {010}, {110} |
| Physical Properties | |
| Mohs hardness | not defined |
| Density (g / cm 3 ) | measured: 3.36; calculated: 3.44 to 3.48 |
| Cleavage | completely after {001}, clearly after {100} |
| Break ; Tenacity | not defined |
| colour | colorless |
| Line color | White |
| transparency | transparent |
| shine | Glass gloss, silk gloss in aggregates |
| Crystal optics | |
| Refractive indices |
n α = 1.720 to 1.740 n β = 1.790 to 1.800 n γ = 1.850 to 1.900 |
| Birefringence | δ = 0.130 to 0.160 |
| Optical character | biaxial negative |
| Axis angle | 2V = 85 ° (measured); 80 to 82 ° (calculated) |
| Other properties | |
| Chemical behavior | soluble in warm hydrochloric acid |
Sabinaite is a very rarely occurring mineral from the mineral class of " carbonates and nitrates " (formerly carbonates, nitrates and borates, see classification ). It crystallizes in the monoclinic crystal system with the composition Na 4 Zr 2 Ti [O | CO 3 ] 4 , so it is chemically a sodium - zirconium - titanium carbonate.
Sabinaite is colorless and transparent and only develops small, pseudo-hexagonal crystals a few tenths of a millimeter in diameter with a flaky to scaly habit and a glass-like sheen on the surfaces. It is usually found in the form of compact, chalky and silky shimmering mineral aggregates and powdery crusts.
Etymology and history
Sabinaite was first discovered in the "Francon" quarry near Montreal in Canada and described in 1980 by John Leslie Jambor , B. Darko Sturman and GC Weatherly, who named the mineral after the mineralogist Ann Phyllis Sabina Stenson (* 1930). By collecting sufficient quantities of the mineral, she made it possible to precisely characterize it.
classification
In the meanwhile outdated, but still in use 8th edition of the mineral classification according to Strunz , the sabinaite belonged to the common mineral class of "carbonates, nitrates and borates" and to the department of "anhydrous carbonates with foreign anions ", where it was the only member of the unnamed group V / C.05 formed.
The 9th edition of Strunz's mineral systematics , which has been in effect since 2001 and is used by the International Mineralogical Association (IMA), assigns the sabinaite to the newly defined class of "carbonates and nitrates" (the borates form a separate class here), but also in the department of “carbonates with additional anions; without H 2 O “. This is further subdivided according to the predominant cations in the compound , so that the mineral can be found according to its composition in the sub-section “With alkalis etc.”, where it is the only member of the unnamed group 5.BB.20 .
The systematics of minerals according to Dana , which is mainly used in the English-speaking world , assigns the Sabinaite, like the outdated Strunz system, to the common class of “carbonates, nitrates and borates” and there to the “carbonates - hydroxyl or halogen” class. Here he is the only member of the unnamed group 16a.05.04 within the sub-section “Carbonates - Hydroxyl or Halogen with Different Formulas”.
Education and Locations
Sabinait forms in dawsonithaltigen Silicocarbonatiten and in cavities of sodalite - syenites . In addition to dawsonite and sodalite, aegirine , albite , analcime , anchorite , barite , calcite , dolomite , galena , ilmenorutil , cryolite , microcline , pectolite , pyrite , quartz , siderite and weloganite can occur as accompanying minerals .
In addition to its type locality, the “Francon” quarry near Montreal, only the “Poudrette” quarry on Mont Saint-Hilaire in Canada is known to be the site of sabinaite (as of 2013) .
Crystal structure
Sabinaite crystallizes monoclinically in the space group C 2 / c (space group no. 15) with the lattice parameters a = 10.20 Å ; b = 6.62 Å; c = 17.96 Å and β = 94.1 ° as well as 4 formula units per unit cell .
See also
literature
- JL Jambor, BD Sturman, GC Weatherly: Sabinaite, a new anhydrous zirconium-bearing carbonate mineral from Montreal Island, Québec , In: The Canadian Mineralogist , Volume 18, pp. 25-29
Web links
Individual evidence
- ↑ a b c d e Hugo Strunz , Ernest H. Nickel: Strunz Mineralogical Tables . 9th edition. E. Schweizerbart'sche Verlagbuchhandlung (Nägele and Obermiller), Stuttgart 2001, ISBN 3-510-65188-X , p. 296 .
- ↑ Webmineral - Sabinaite
- ↑ a b Sabinaite , In: John W. Anthony, Richard A. Bideaux, Kenneth W. Bladh, Monte C. Nichols (Eds.): Handbook of Mineralogy, Mineralogical Society of America , 2001 ( PDF 67.1 kB )
- ↑ a b c Mindat - Sabinaite
- ↑ Find location list for Sabinaite at the Mineralienatlas and at Mindat