Abhurit

from Wikipedia, the free encyclopedia
Abhurit
Abhurite - Shipwreck Hydra, South coast of Norway.jpg
Brownish tabular abhurite crystals from the shipwreck "Hydra", south coast of Norway (image width 5 mm)
General and classification
other names
  • IMA 1983-061
  • Tin oxyhydroxy chloride
chemical formula Sn 21 O 6 (OH) 14 Cl 16
Mineral class
(and possibly department) 		Halides
System no. to Strunz
and to Dana 		3.DA.30
10.05.09.01
Crystallographic Data
Crystal system trigonal
Crystal class ; symbol trigonal trapezoidal; 32
Space group R 32 (No. 155)Template: room group / 155
Lattice parameters a  = 10.02  Å ; c  = 44.01 Å
Formula units Z  = 3
Twinning after {001}
Physical Properties
Mohs hardness 2
Density (g / cm 3 ) measured: 4.42 (synthetic); calculated: 4.417
Cleavage no
Break ; Tenacity hooked
colour colorless
Line color White
transparency transparent
shine Glass gloss, opalescent
Crystal optics
Refractive indices n ω  = 2.060
n ε  = 2.110
Birefringence δ = 0.050
Optical character uniaxial positive

Abhurite is a very rarely occurring mineral from the mineral class of " halides ". It crystallizes in the trigonal crystal system with the chemical composition Sn 21 O 6 (OH) 14 Cl 16 , i.e. chemically speaking it corresponds to a basic tin chloride.

Abhurite mostly develops thin-tabular, hexagonal crystals , but is also found in the form of cryptocrystalline crusts. The largest colorless and transparent crystals found so far were in the form of small, hexagonal tablets about two millimeters in size.

Etymology and history

Abhurit was first discovered in 1983 in an approximately one hundred year old shipwreck in the bay "Sharm Abhur" about 30 km north of Jeddah (English Jiddah ) on the Red Sea in Saudi Arabia . The mineral formed there as a result of the corrosion of the sunken tin bars. Abhurit is the only known type mineral from Saudi Arabia to date.

Abhurite was analyzed and described by John J. Matzko, Howard T. Evans Jr., Mary E. Mrose, Philip Aruscavage, who named the mineral after its type locality and submitted their results to the International Mineralogical Association (IMA) for examination of the mineral status ( Register no.IMA 1983-061 ). This recognized the mineral status and the chosen name in the same year, which, however, no longer corresponds to the rules of the IMA, which have been in force since 1998, according to which material of anthropogenic origin (substances created, caused, produced or influenced by humans) such as corroded human artifacts are not considered Mineral is accepted.

Type material of the mineral is located in the Royal Ontario Museum of Toronto in Canada and in the National Museum of Natural History in Washington, DC in the United States (Register No. 162403).

classification

Since the Abhurit was only discovered in 1983 and recognized as an independent mineral, it is not yet listed in the outdated 8th edition of the mineral classification according to Strunz . Only in the Lapis mineral directory , which was revised and updated in 2018 by Stefan Weiß, which is still based on this classic system from Karl Hugo Strunz out of consideration for private collectors and institutional collections , the mineral received the system and mineral number. III / D.05-10 . In the "lapis system" this corresponds to the class of "halides" and there the department "oxyhalides", where abhurite together with panichiite forms an independent, but unnamed group.

The 9th edition of Strunz's mineral systematics , which has been valid since 2001 and updated by the IMA until 2009, also assigns the Abhurit to the “halides” class and there to the “oxyhalides, hydroxyhalides and related double halides”. 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 etc., without Pb”, where it is the only member of the unnamed group 3.DA.30 .

The systematics of minerals according to Dana , which is mainly used in the English-speaking world , assigns the Abhurit to the “halides” class and there to the “oxyhalides and hydroxyhalides”. Here he is to be found as the only member of the unnamed group 10.05.09 within the subdivision "Oxyhalides and hydroxyhalides with the formula A m (O, OH) p X q ".

Crystal structure

Abhurite crystallizes trigonal in the space group R 32 (space group no. 155) with the lattice parameters a  = 10.02  Å and c  = 44.01 Å and 3 formula units per unit cell . Template: room group / 155

Education and Locations

Abhurite forms as bubble-shaped efflorescence on the surface of tin under the influence of sea water. Accompanying minerals include romarchite , hydroromarchite , kutnohorite and aragonite .

As a very rare mineral formation, Abhurite could so far (as of 2011) only be detected in a few samples at fewer than 10 sites. In addition to its type locality Sharm Abhur in Saudi Arabia, these are also an unspecified site near Port Royal in Jamaica as well as shipwrecks near Hidra / Flekkefjord in Norway, St Ives (England) and Anglesey (Wales) in the United Kingdom and San Jose ( Monroe County ) and Beaufort in the United States.

See also

literature

  • HG Von Schnering, R. Nesper, H. Pelshenke: Sn 21 Cl 16 (OH) 14 O 6 , the so-called basic tin (II) chloride. In: Journal of Nature Research B . 36, 1981, pp. 1551-1560 ( PDF , free full text).
  • John J. Matzko, Howard T. Evans Jr., Mary E. Mrose, Philip Aruscavage: Abhurite, a new tin hydroxychloride mineral, and a comparative study with a synthetic basic tin chloride . In: The Canadian Mineralogist . tape 23 , 1985, pp. 233–240 (English, rruff.info [PDF; 2.1 MB ; accessed on June 28, 2019]).
  • R. Edwards, RD Gillard, PA Williams: The stabilities of secondary tin minerals: abhurite and its relationships to Sn (II) and Sn (IV) oxides and oxyhydroxides . In: Mineralogical Magazine . tape 56 , 1992, pp. 221–226 (English, rruff.info [PDF; 390 kB ; accessed on June 28, 2019]).
  • Stacie E. Dunkle, James R. Craig, J. Donald Rimstidt, Wayne R. Lusardi: Romarchite, Hydroromarchite and Abhurite formed during the corrosion of Pewter Artifacts from the Queen Anne's Revenge . In: The Canadian Mineralogist . tape 41 , 2003, p. 659–669 , doi : 10.2113 / gscanmin.41.3.659 (English, rruff.info [PDF; 1.9 MB ; accessed on June 28, 2019]).

Web links

Commons : Abhurite  - collection of images, videos and audio files

Individual evidence

  1. ↑ a b c d e 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.  172 (English).
  2. ↑ David Barthelmy: Abhurite MineralData. In: webmineral.com. Retrieved June 28, 2019 .
  3. ↑ a b c Abhurite . 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; 69  kB ; accessed on June 28, 2019]).
  4. ↑ a b c Abhurite. In: mindat.org. Hudson Institute of Mineralogy, accessed June 28, 2019 .
  5. ^ Stefan Schorn and other authors: Sharm Abhur, Province of Jiddah, Saudi Arabia. In: mineralienatlas.de. Mineral Atlas - Fossil Atlas , accessed June 28, 2019 .
  6. ↑ Type locality Saudi Arabia (English Saudi Arabia ). In: mindat.org. Hudson Institute of Mineralogy, accessed June 28, 2019 .
  7. ^ Ernest H. Nickel, Joel D. Grice: The IMA Commission on new Minerals and Mineral Names: Procedures and Guidelines on Mineral Nomenclature, 1998 . In: The Canadian Mineralogist . tape 36 , 1998, pp. 2 (English, cnmnc.main.jp [PDF; 336 kB ; accessed on June 28, 2019]).
  8. ↑ 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 .
  9. ↑ Ernest H. Nickel, Monte C. Nichols: IMA / CNMNC List of Minerals 2009. (PDF 1703 kB) In: cnmnc.main.jp. IMA / CNMNC, January 2009, accessed June 28, 2019 .
  10. ↑ Mindat - Number of localities for Abhurit