Berlinite (mineral)
| Berlinite | |
|---|---|
 |
|
| General and classification | |
| other names |
Aluminum orthophosphate ( aluminum phosphate for short ) |
| chemical formula | Al [PO 4 ] |
|
Mineral class (and possibly department) |
Phosphates, arsenates, vanadates |
|
System no. to Strunz and to Dana |
8.AA.05 ( 8th edition : VII / A.01) 04/38/02/01 |
| Crystallographic Data | |
| Crystal system | trigonal |
| Crystal class ; symbol | trigonal trapezoidal; 32 or completely 321 or 312 |
| Space group | P 3 1 21 (No. 152) or P 3 2 21 (No. 154) |
| Lattice parameters | see crystal structure |
| Formula units | Z = 3 |
| Physical Properties | |
| Mohs hardness | ≈ 6.5 |
| Density (g / cm 3 ) | measured: 2.64 to 2.66; calculated: 2.618 |
| Cleavage | is missing |
| Break ; Tenacity | shell-like |
| colour | colorless, gray-pink to light pink |
| Line color | White |
| transparency | transparent to translucent |
| shine | Glass gloss |
| Crystal optics | |
| Refractive indices |
n ω = 1.524 n ε = 1.532 |
| Birefringence | δ = 0.008 |
| Optical character | uniaxial positive |
| Other properties | |
| Special features | occasionally dark red fluorescence |
Berlinite is a rarely occurring mineral from the mineral class of " phosphates , arsenates and vanadates " with the chemical composition Al [PO 4 ] and is therefore an aluminum orthophosphate from a chemical point of view .
Berlinite crystallizes in the trigonal crystal system and develops predominantly fibrous, radially radiated or granular to massive mineral aggregates with a glass-like sheen on the surfaces. In its pure form it is colorless and transparent. However, due to multiple refraction due to lattice construction defects or polycrystalline formation, it can also appear white and, due to foreign admixtures, take on a gray-pink to light pink color, with the transparency decreasing accordingly.
Etymology and history
Berlinite was first discovered in the Västanå mine near Näsum in the Swedish municipality of Bromölla and described in 1868 by Christian Wilhelm Blomstrand . He named the mineral after Professor Nils Johan Berlin (1812-1891), a Swedish professor of chemistry and mineralogy in Lund and Uppsala.
classification
In the 8th edition of the mineral systematics according to Strunz , which is out of date, but still in use , berlinite belonged to the division of "Anhydrous phosphates [PO 4 ] 3− , without foreign anions ", where together with alarsite , beryllonite , hurlbutite , lithiophosphate , nalipoite , Olympit and Rodolicoit the unnamed group with the addition "Small cations (Li, Be, Al, Fe3 +)" and the system no. VII / A.01 .
The 9th edition of Strunz's mineral systematics , which has been in effect since 2001 and is used by the International Mineralogical Association (IMA), also assigns berlinite to the category of “phosphates etc. without additional anions; without H 2 O “. This is, however, further subdivided according to the relative size of the cations , so that the mineral can be found according to its composition in the sub-section “With small cations (some with larger cations)”, where it is the unnamed group only together with Alarsite and Rodolicoite 8.AA.05 forms.
The systematics of minerals according to Dana , which is mainly used in the English-speaking world , assigns berlinite to the class of "phosphates, arsenates and vanadates" and there in the department of "anhydrous phosphates etc.". Here he is the namesake in the " Berlinit group " with the system no. 38.04.02 and the other members Alarsit and Rodolicoit can be found in the sub-section "Anhydrous phosphates etc., A + XO 4 ".
Crystal structure
Berlinite crystallized in the trigonal crystal system and is similar to quartz mirror image left and right molds, wherein the links form with the space group P 3 1 21 (space group no. 152) and form with space group P 3 2 21 (no. 154) circumscribed becomes. Both space groups belong to the same class, with the twofold axis parallel [100].
For the left form the measurement of the lattice parameters for a = 4.9458 Å and c = 10.9526 Å and for the right form the lattice parameters a = 4.9438 Å and c = 10.9498 Å with three formula units per unit cell .
Berlinite is homeotype with quartz, which means that both crystallize in the same space group but with different lattice parameters. see crystal structure of quartz .
properties
Under UV light , some berlinites show a dark red fluorescence , similar to that of neon-colored highlighters .
Education and Locations
Berlinite is formed at high temperatures in the hydrothermal solutions or by metasomatism and enters Paragenesis with Augelith and Attakolith and often fused with scorzalite or trolleite on.
As a rare mineral formation, Berlinite has so far (as of 2013) only been found at a few sites, with around 20 sites being known. In addition to its type locality , the Västanå mine near Näsum , the mineral also appeared in Sweden at the Hålsjöberg quarry (Horrsjöberg) near Torsby .
In Germany, berlinite was found in a basalt quarry near Wiesau -Triebendorf in Bavaria and in the "Sauberg" pit near Ehrenfriedersdorf in Saxony.
The only known site in Switzerland so far is Törbel in the canton of Valais.
Other sites include the “Paddy's River Cu Mine” on the Cotter River and Mount Perry in the North Burnett region in Australia, the “Sapucaia Mine” near Sapucaia do Norte and the “Poço d'Antas” mine field in the Piauí Valley in Brazil State of Minas Gerais , in the Itremo massif (Tsiambenana quarry) in the Ambatofinandrahana district in Madagascar, in several places in the Gatumba district in the western province of Rwanda , in the Cioclovina cave in the Romanian district of Hunedoara , at the Cap de Creus in Spain, near Zlaté Hory ( German Zuckmantel ) in the Czech Republic as well as the "Inspiration Mine" in the Miami-Inspiration district in Gila County (Arizona) and Washington County (Maine) in the USA.
See also
literature
- CW Blomstrand: Om Westanå mineralier . In: Öfversigt af Kongliga Vetenskaps-Akademiens Förhandlingar . tape 25 , 1868, p. 197–212 (Swedish, rruff.info [PDF; 933 kB ; accessed on September 30, 2017]).
- Friedrich Klockmann : Klockmann's textbook of mineralogy . Ed .: Paul Ramdohr , Hugo Strunz . 16th edition. Enke, Stuttgart 1978, ISBN 3-432-82986-8 , pp. 622 (first edition: 1891).
- Helmut Schrätze , Karl-Ludwig Weiner : Mineralogy. A textbook on a systematic basis . de Gruyter, Berlin; New York 1981, ISBN 3-11-006823-0 , pp. 609-610 .
- Y. Muraoka, K. Kihara: The temperature dependence of the crystal structure of berlinite, a quartz-type form of AlPO 4 . In: Physics and Chemistry of Minerals . tape 24 , no. 4 , 1997, p. 243-253 , doi : 10.1007 / s002690050036 .
Web links
Individual evidence
- ↑ a b c Webmineral - Berlinite (English)
- ↑ a b c American Mineralogist Crystal Structure Database - Berlinite (English, left form P 3 1 21 : 2007, legal form P 3 2 21 : 1997)
- ↑ a b Berlinite . In: John W. Anthony, Richard A. Bideaux, Kenneth W. Bladh, Monte C. Nichols (Eds.): Handbook of Mineralogy, Mineralogical Society of America . 2001 ( handbookofmineralogy.org [PDF; 62 kB ; accessed on September 30, 2017]).
- ↑ a b c Mindat - Berlinite
- ↑ Mindat - Number of localities for Berlinit
- ↑ Find location list for berlinite in the Mineralienatlas and Mindat