Nasinite

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Nasinite
General and classification
chemical formula Na 2 [B 5 O 8 (OH)] • 2H 2 O
Mineral class
(and possibly department) 		Borates (formerly carbonates, nitrates and borates)
System no. to Strunz
and to Dana 		6.EC.05 ( 8th edition : V / K.03)
05/26/06/01
Crystallographic Data
Crystal system orthorhombic
Crystal class ; symbol orthorhombic-pyramidal; mm 2
Room group (no.) Pna 2 1 (No. 33)
Lattice parameters a  = 12.02  Å ; b  = 6.52 Å; c  = 11.17 Å
Formula units Z  = 4
Physical Properties
Mohs hardness not defined
Density (g / cm 3 ) measured: 2.2; calculated: 2.134
Cleavage not defined
Break ; Tenacity not defined
colour white, yellow, yellow-orange
Line color White
transparency translucent
shine not defined
Crystal optics
Refractive indices n α  = 1.494
n β  = 1.512
n γ  = 1.524
Birefringence δ = 0.030
Optical character biaxial negative
Axis angle 2V = 66 ° (measured); 76 ° (calculated)

Nasinite is an extremely rare mineral from the mineral class of " borates " (formerly carbonates, nitrates and borates, see classification ). It crystallizes in the orthorhombic crystal system with the composition Na 2 [B 5 O 8 (OH)] · 2H 2 O, so it is chemically a water-containing sodium borate.

So far, nasinite could only be discovered in the form of tiny, tabular to needle-like, pseudo-hexagonal crystals or microcrystalline crystal groups and earthy masses of white, yellow and yellow-orange color.

Etymology and history

Nasinite was first discovered near Larderello in the central Italian region of Tuscany and was described in 1961 by Curzio Cipriani and Piero Vannuccini , who named the mineral after the Italian chemist Raffaello Nasini (1854-1931).

classification

In the 8th edition of the mineral classification according to Strunz , which is now outdated, but still in use , the nasinite belonged to the common mineral class of "carbonates, nitrates and borates" and there to the department of "layer borates with complex assemblies [B x (O, OH) y ]" , where he formed the unnamed group V / K.03 together with Biringuccit and Tuzlait .

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 nasinite to the now independent class of "borates" and there in the department of "pentaborates". This is, however, further subdivided according to the crystal structure, so that the mineral can be found according to its structure in the sub-section "Layer pentaborate (phyllo-pentaborate)", where together with biringuccite ​​the "biringuccite ​​group" with the system no. 6.EC.05 forms.

The systematics of minerals according to Dana , which is mainly used in the English-speaking area , assigns the nasinite, like the outdated Strunz system, to the common class of "carbonates, nitrates and borates" and there to the department and subdivision of the same name of "hydrous borates with hydroxyl or halogen" a. Here he can be found as the only member of the unnamed group 05/26/06 .

Education and Locations

At its type locality Larderello, nasinite was in close paragenesis with biringuccite ​​as encrustations on pipelines to the so-called "Hole of the Storehouse", which was drilled in 1927 near Lardarello. Larderello is also the only place where nasinite was found so far (as of 2013). Auripigment , Thénardite and quartz also appeared as further parageneses .

Crystal structure

Nasinit crystallizes orthorhombically in the space group Pna 2 1 (space group no. 33) with the lattice parameters a  = 12.02  Å ; b  = 6.52 Å and c  = 11.17 Å and 4 formula units per unit cell .

See also

literature

  • Curzio Cipriani, Piero Vannuccini: Hoeferite [= biringuccite] e nasinite: due nuori borati fra i prodotti di Lardarello , In: Accademia Nazionale dei Lincei, Rendiconti della Classe di Scienze Fisiche, Matematiche e Naturali , Series VIII 30 (1962), p. 74
  • Michael Fleischer: New Mineral Names , In: American Mineralogist , Volume 48 (1963), pp. 708–712 ( PDF 381.8 kB ; Biringuccit (Mineral A) / Nasinite (Mineral B) from p. 2)
  • E. Corazza, S. Menchetti, C. Sabelli: The crystal structure of nasinite, Na 2 [B 5 O 8 (OH)] · 2H 2 O , In: Acta Crystallographica Section B. Structural Crystallography and Crystal Chemistry , Volume 31 / 10 (October 1975); accessible online at scripts.iucr.org

Web links

Individual evidence

  1. ↑ a b c d e f 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.  351 .
  2. ↑ Webmineral - Nasinite
  3. ↑ a b Nasinite , In: John W. Anthony, Richard A. Bideaux, Kenneth W. Bladh, Monte C. Nichols (Eds.): Handbook of Mineralogy, Mineralogical Society of America , 2001 ( PDF 65.1 kB )
  4. ↑ a b c d Mindat - Nasinite