Glaucosphere
| Glaucosphere | |
|---|---|
 |
|
| General and classification | |
| other names |
|
| chemical formula |
|
|
Mineral class (and possibly department) |
Carbonates and nitrates |
|
System no. to Strunz and to Dana |
5.BA.10 ( 8th edition : V / C.01) 16a.03.01.02 |
| Crystallographic Data | |
| Crystal system | monoclinic |
| Crystal class ; symbol | monoclinic prismatic; 2 / m |
| Space group | P 2 1 / a (No. 14, position 3) |
| Lattice parameters |
a = 9.35 Å ; b = 11.97 Å; c = 3.13 Å β = 96 ° |
| Formula units | Z = 4 |
| Physical Properties | |
| Mohs hardness | 3 to 4 |
| Density (g / cm 3 ) | measured: 3.78 to 3.96; calculated: 3.78 to 4.03 |
| Cleavage | parallel to the c-axis [001] |
| Break ; Tenacity | brittle |
| colour | green (dark malachite green to apple green) |
| Line color | light green |
| transparency | translucent |
| shine | weak glass gloss to matt; Silky shine on fibrous aggregates |
| Crystal optics | |
| Refractive indices |
n α = 1.690 to 1.710 n β = 1.830 to 1.850 n γ = 1.830 to 1.850 |
| Birefringence | δ = 0.140 |
| Optical character | biaxial negative |
Glaukosphärit is a rarely occurring minerals from the mineral class of "carbonates and nitrates" with the idealized chemical composition CuNi (CO 3 ) (OH) 2 and chemically seen a copper - nickel - carbonate with additional hydroxide .
Glaucosphere crystallizes in the monoclinic crystal system and is mostly found in the form of fibrous to concentric zonal spheres up to about three millimeters in size, but also occurs in clumsy mineral aggregates or less often as felt masses with parallel crystal fibers. The translucent crystals and aggregates are from dark malachite-green to apple-green in color and show a weak glass-like sheen on the surfaces or are matt. Fibrous aggregates, on the other hand, shimmer more like silk .
Etymology and history
Glaucosphere was discovered for the first time in the Kambalda nickel deposit , more precisely at Hampton East Location 48 , in the administrative region of Coolgardie Shire in the Australian state of Western Australia. The first description was in 1974 by MW Pryce and J. Just, who used the mineral based on its color and crystal formation after the ancient Greek words Γλαύκος glaukós for sparkling, shiny, luminous, meaning the bright shine of the sky, the sea or the human eye and with regard to the color leaves a certain leeway and named σφαῖρα sphaira for ball.
Type material of the mineral is in the Western Australian Museum in Perth (Australia) under the catalog no. MDC5309 , in the Mines ParisTech (also École des mines ) in Paris (France), in the Natural History Museum in London (England) and the catalog no. 1975,419 as well as in the National Museum of Natural History in Washington, DC (USA) and the catalog no. 131889 kept.
classification
In the outdated, but partly still in use, 8th edition of the mineral classification according to Strunz , the glaucoma belonged to the common mineral class of "carbonates, nitrates and borates" and there to the department "anhydrous carbonates with foreign anions ", where it together with aurichalcite , azurite , brianyoungite , Chukanovite , Georgeit , Hydrozinkit , Kolwezit , Loseyit , Malachit , Mcguinnessit , Nullaginit , Pokrovskit , Rosasit , Sclarit and Zinc Rosasit the "Azurit-Rosasit-series" with the system no. V / C.01 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 glaucoma to the newly defined class of "carbonates and nitrates" (the borates form a separate class here), but also in there the department of “carbonates with additional anions; without H 2 O “. This is further subdivided according to the predominant metals in the compound, so that the mineral can be found according to its composition in the sub-section "With Cu, Co, Ni, Zn, Mg, Mn", where it is found together with Chukanovite, Georgeit, Kolwezit, Malachite, mcguinnessite, nullaginite, Pokrovskite, rosasite and zinc rosasite form the "malachite group" with system no. 5.BA.10 forms.
The systematics of minerals according to Dana , which is mainly used in the English-speaking world , assigns the glaucoma, like the outdated Strunz system, to the common class of "carbonates, nitrates and borates" and there to the category of "carbonates - hydroxyl or halogen". Here he is in the " Rosasite group " with the system no. 16a.03.01 within the subsection “Carbonates - Hydroxyl or Halogen with (AB) 2 (XO) 3 Z q ”.
Crystal structure
Glaucosphere crystallizes monoclinically in the space group P 2 1 / a (space group no. 14, position 3) with the lattice parameters a = 9.35 Å ; b = 11.97 Å; c = 3.13 Å and β = 96 ° and 4 formula units per unit cell .
Education and Locations
Glaukosphärit forms as rare secondary mineral in the oxidation zone of copper-nickel sulphide - deposits . As Begleitminerale occur among other azurite , Brochantite , Carrboydit , Chalkonatronit , Epsomite , gaspeite , Georgeit , gypsum , goethite , népouite , Paratacamit , quartz and Takovite and nickel-containing varieties of chrysotile , magnesite , malachite and seladonite on.
As a rare mineral formation, glaucoma has only been found at a few sites, although around 30 sites have been documented so far (as of 2018). In addition to its type locality , the Hampton East location 48 about three kilometers north of the Durkin shaft , in the nickel mine of the same name near Kambalda , the mineral was also found in the nearby nickel mines Otter Shoot and Jan and in other mines near Widgiemooltha in Coolgardie Shire , near Bardoc in the administrative region of Kalgoorlie-Boulder City , at Laverton in the Laverton Shire of the same name and at Menangina in Menzies Shire in the state of Western Australia.
The only known sites in Germany so far are the Kronewald and Jakobskrone pits near Achenbach in the Siegerland of North Rhine-Westphalia.
In Austria, glaucoma has so far only occurred in the heaps and tunnels of the polymetallic sulphide deposit Vogelhalt on the Vogel Alp in the Salzburg municipality of Leogang and in the Stockerstollen on the Silberberg in the Brixlegg - Rattenberg mining area and near Flirsch in the Stanzer Valley in Tyrol.
The only site in Switzerland to date is the former Plantorin nickel-cobalt mine in the municipality of Ayer in Val d'Anniviers in the canton of Valais.
Other well-known sites are in France, Greece, Japan, the Democratic Republic of the Congo, Romania, Spain, South Africa and the United States of America.
See also
literature
- MW Pryce, J. Just: Glaukosphaerite: A new nickel analogue of rosasite . In: Mineralogical Magazine . tape 39 , no. 307 , September 1974, p. 737–743 (English, rruff.info [PDF; 811 kB ; accessed on December 22, 2018]).
- John Leslie Jambor : A possible unit cell for glaukosphaerite . In: The Canadian Mineralogist . tape 14 , no. 4 , 1976, p. 574-576 (English).
Web links
- Mineral Atlas: Glaucosphere (Wiki)
Individual evidence
- ^ Friedrich Klockmann : Klockmanns textbook of mineralogy . Ed .: Paul Ramdohr , Hugo Strunz . 16th edition. Enke, Stuttgart 1978, ISBN 3-432-82986-8 , pp. 838 (first edition: 1891).
- ↑ a b c IMA / CNMNC List of Mineral Names; November 2018 (English; PDF 1.7 MB)
- ↑ a b c d Hugo Strunz , Ernest H. Nickel : Strunz Mineralogical Tables. Chemical-structural Mineral Classification System . 9th edition. E. Schweizerbart'sche Verlagbuchhandlung (Nägele and Obermiller), Stuttgart 2001, ISBN 3-510-65188-X , p. 294 (English).
- ↑ David Barthelmy: Glaukosphaerite Mineral Data. In: webmineral.com. Retrieved December 21, 2018 .
- ↑ a b c d e f Glaukosphaerite . In: John W. Anthony, Richard A. Bideaux, Kenneth W. Bladh, Monte C. Nichols (Eds.): Handbook of Mineralogy, Mineralogical Society of America . 2001 (English, handbookofmineralogy.org [PDF; 66 kB ; accessed on December 21, 2018]).
- ↑ a b c d Number of sites for glaucosphaerites. In: mindat.org. Hudson Institute of Mineralogy, accessed December 21, 2018 .
- ↑ Hans Lüschen: The names of the stones. The mineral kingdom in the mirror of language . 2nd Edition. Ott Verlag, Thun 1979, ISBN 3-7225-6265-1 , p. 227 .
- ^ Glaucosphaerites. In: mindat.org. Hudson Institute of Mineralogy, accessed December 21, 2018 .
- ↑ Find location list for glaucoma in the Mineralienatlas and in Mindat