Smrkovecit
| Smrkovecit | |
|---|---|
 |
|
| General and classification | |
| other names |
IMA 1993-040 |
| chemical formula |
|
|
Mineral class (and possibly department) |
Phosphates, arsenates and vanadates |
|
System no. to Strunz and to Dana |
8.BO.15 11.11.06.01 |
| Crystallographic Data | |
| Crystal system | monoclinic |
| Crystal class ; symbol | monoclinic prismatic; 2 / m |
| Space group | P 2 1 / c (No. 14) |
| Lattice parameters |
a = 6.954 (6) Å ; b = 7.494 (4) Å; c = 10.869 (6) Å β = 107.00 ° |
| Formula units | Z = 4 |
| Physical Properties | |
| Mohs hardness | 4 to 5 |
| Density (g / cm 3 ) | calculated: [6.69] |
| Cleavage | indistinct after {010} |
| Break ; Tenacity | slightly mussel-like |
| colour | white, light yellow |
| Line color | White |
| transparency | transparent to translucent |
| shine | Glass to diamond gloss |
| Crystal optics | |
| Refractive indices |
n α = 2.050 n β = 2.060 n γ = 2.090 |
| Birefringence | δ = 0.040 |
| Optical character | biaxial positive |
| Axis angle | 2V = 58 ° to 61 ° (measured), 62 ° (calculated) |
Smrkovecit is a very rarely occurring minerals from the mineral class of "phosphates, arsenates, and vanadates" with the chemical composition of Bi 2 [O | OH | PO 4 ] and is therefore chemically seen a bismuth - phosphate with additional oxygen - and hydroxide ions .
Smrkovecite crystallizes in the monoclinic crystal system , but only develops tiny crystals up to 0.1 mm in size with a glass-like to diamond-like sheen on the surfaces. Similar to atelestite , smrkovecite is also found in wart-shaped to spherical aggregate forms .
The transparent to translucent crystals are white to light yellow in color, which can also be zoned. Its line color is white.
Etymology and history
Smrkovecite was first discovered in a uranium-bismuth-silver mine near the former settlement of Smrkovec (German: Schönficht ) in Slavkovský les ( Kaiserwald ) in the Czech region of Karlovarský kraj ( Karlsbad ). The first description was made by Tomáš Řídkošil, Jiří Sejkora and Vladimír Šrein, who named the mineral according to its type locality and submitted it to the International Mineralogical Association (IMA) for examination in 1993 (internal receipt number of the IMA: 1993-040). After recognition by the IMA as an independent mineral species, the first description was published in 1996 in the journal New Yearbook for Mineralogy, monthly books .
The type material of the mineral is in the National Museum in Prague under the catalog no. P1N84596 retained .
classification
Since the Smrkovecite was only recognized as an independent mineral in 1993, it is not yet listed in the 8th edition of the mineral classification according to Strunz , which has been outdated since 1977 . Only in the Lapis mineral directory according to Stefan Weiß, which, out of consideration for private collectors and institutional collections, is still based on this old form of Karl Hugo Strunz's system , was the mineral given the system and mineral number. VII / B.30-01 . In the "lapis system" this corresponds to the class of "phosphates, arsenates and vanadates" and there the department "anhydrous phosphates, with foreign anions F, Cl, O, OH", where smrkovecite together with atelestite , hechtsbergite , petitjeanite , priceingerite , Schlegelit and Schumacherit form an independent but unnamed group (as of 2018).
The 9th edition of Strunz's mineral systematics , which has been in effect since 2001 and was updated by the IMA until 2009, also assigns Smrkovecit to the category of “phosphates etc. with additional anions; without H 2 O “. However, this is further subdivided according to the relative size of the cations involved and the molar ratio of the additional anions (OH etc.) to the phosphate, arsenate or vanadate complex (RO 4 ), so that the mineral is classified in the subsection “With only large Cations; (OH etc.): RO 4 ≥ 1: 1 "can be found, where together with atelestite and hechtsbergite the" atelestite group "with the system no. 8.BO.15 forms.
The systematics of minerals according to Dana , which is mainly used in the English-speaking world , assigns Smrkovecit to the class of "phosphates, arsenates and vanadates" and there in the category of "anhydrous phosphates etc., with hydroxyl or halogen". Here he is together with Hechtsbergit in the " Smrkovecitgruppe " with the system no. 41.11.06 within the subsection "Anhydrous phosphates etc., with hydroxyl or halogen with different formulas".
Chemism
The theoretical composition of smrkovecite (Bi 2 [O | OH | PO 4 ]) contains 76.56% bismuth (Bi), 5.67% phosphorus (P), 17.58% oxygen (O) and 0.18% hydrogen (H).
In the analyzed mineral samples from Smrkovec there were also small foreign admixtures of 0.17% arsenic in the form As 2 O 5 , 0.03% vanadium in the form V 2 O 5 and 0.02% silicon dioxide (SiO 2 ).
Crystal structure
Smrkovecite crystallizes monoclinically in the space group P 2 1 / c (space group no. 14) with the lattice parameters a = 6.954 (6) Å ; b = 7.494 (4) Å; c = 10.869 (6) Å and β = 107.00 ° as well as 4 formula units per unit cell .
Education and Locations
Smrkovecit formed secondarily by weathering and can be found among others in ancient duty recovery or waste dumps of Ag-Bi-As-U deposits depleting mines. Atelestite, bismuthite , bismuth ferrite , eulytin , metatorbernite , petitjeanite, prizingerite, pucherite , quartz , retgersite and sillénite can occur as accompanying minerals .
Apart from its type locality Smrkovec, the mineral has so far (as of 2019) only been discovered in the Jáchymov mining district ( Sankt Joachimsthal ) located about 40 km to the northeast .
See also
literature
- T. Řídkošil, Jiří Sejkora and V. Šrein: Smrkovecite, monoclinic Bi 2 O (OH) (PO 4 ), a new mineral of the atelestite group . In: New yearbook for mineralogy, monthly books . 1996, p. 97-102 ( brief description from researchgate.net [accessed June 10, 2018]).
- John Leslie Jambor , Vladimir A. Kovalenker, Jacek Puziewics, Andrew C. Roberts: New mineral names . In: American Mineralogist . tape 81 , 1996, pp. 1282–1286 (English, rruff.info [PDF; 494 kB ; accessed on December 21, 2019]).
Web links
- Mineral Atlas: Smrkovecite (Wiki)
Individual evidence
- ^ A b 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. 468 (English).
- ↑ Malcolm Back, William D. Birch, Michel Blondieau and others: The New IMA List of Minerals - A Work in Progress - Updated: November 2019. (PDF 1720 kB) In: cnmnc.main.jp. IMA / CNMNC, Marco Pasero, November 2019, accessed December 21, 2019 .
- ^ A b David Barthelmy: Smrkovecite Mineral Data. In: webmineral.com. Retrieved December 21, 2019 .
- ↑ a b c T. Řídkošil, Jiří Sejkora and V. Šrein: Smrkovecite, monoclinic Bi 2 O (OH) (PO 4 ), a new mineral of the atelestite group . In: New yearbook for mineralogy, monthly books . 1996, p. 97-102 ( brief description from researchgate.net [accessed December 21, 2019]).
- ↑ a b c d e Smrkovecite . 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; 66 kB ; accessed on December 21, 2019]).
- ↑ a b c d e Smrkovecite. In: mindat.org. Hudson Institute of Mineralogy, accessed December 21, 2019 .
- ↑ Stefan Weiß: The large Lapis mineral directory. All minerals from A - Z and their properties. Status 03/2018 . 7th, completely revised and supplemented edition. Weise, Munich 2018, ISBN 978-3-921656-83-9 .
- ↑ Ernest H. Nickel, Monte C. Nichols: IMA / CNMNC List of Minerals 2009. (PDF 1816 kB) In: cnmnc.main.jp. IMA / CNMNC, January 2009, accessed December 21, 2019 .
- ↑ Find location list for Smrkovecite at the Mineralienatlas and at Mindat , accessed on December 21, 2019.