Sellaite

Sellaite

Sellaite is a magnesium fluoride mineral with formula: MgF2. It crystallizes in the tetragonal crystal system typically as clear to white vitreous prisms. It may be fibrous and occur as radiating aggregates. It has a Mohs hardness of 5 to 6 and a specific gravity of 2.97 to 3.15. Refractive index values are nω = 1.378 and nε = 1.390.

It was first described in 1868 and named for Italian mining engineer and mineralogist Quintino Sella (1827-1884). The type locality is Gébroulaz glacier, Val Thorens, Savoie, Rhône-Alpes, France.

References

* Palache, C., H. Berman, and C. Frondel (1951) "Dana’s system of mineralogy," (7th edition), v. II, pp. 37–39
* [http://webmineral.com/data/Sellaite.shtml Webmineral data]
* [http://www.mindat.org/min-3614.html Mindat with location data]
* [http://rruff.geo.arizona.edu/doclib/hom/sellaite.pdf Mineral Data Publishing PDF]


Wikimedia Foundation. 2010.

Игры ⚽ Поможем решить контрольную работу

Look at other dictionaries:

  • sellaite — ˈseləˌīt noun ( s) Etymology: Italian sellaite, from Quintino Sella died 1884 Italian mineralogist + Italian ite : a mineral MgF2 consisting of magnesium fluoride and occurring in colorless tetragonal prismatic crystals (hardness 5, specific… …   Useful english dictionary

  • sellaite — sel·la·ite …   English syllables

  • FLUORURES NATURELS — Les fluorures naturels constituent les principales combinaisons du fluor dans l’écorce terrestre et pratiquement les seuls minerais exploitables de cet élément. Celui ci se trouve pourtant dans beaucoup d’autres minéraux (apatites, silicates),… …   Encyclopédie Universelle

  • List of minerals S-T (complete) — It is currently not possible to have a complete list of minerals . The International Mineralogical Association is the international group that recognises new minerals and new mineral names, however minerals discovered before 1959 did not go… …   Wikipedia

  • List of minerals — This is a List of minerals for which there are Wikipedia articles. Mineral variety names and mineraloids are to be listed after the valid minerals for each letter.For a complete listing (about 4,000) of all mineral names: List of minerals… …   Wikipedia

  • Magnesium fluoride — Magnesium fluoride[1] Other names …   Wikipedia

  • Geology of Tasmania — Tasmania has a varied geological history, with the world s biggest exposure of diabase, or dolerite. Rocks from the Neoproterozoic, Paleozoic and Mesozoic time periods appear. It is one of the few southern hemisphere areas glaciated during the… …   Wikipedia

  • Isomorphisme (chimie) —  Pour l’article homonyme, voir Isomorphisme.  En chimie du solide, l isomorphisme ou isomorphotropie est la faculté de composés différents de cristalliser avec des mailles de même symétrie et dont les paramètres sont proches, ce qui… …   Wikipédia en Français

  • Isotypisme — Isomorphisme (chimie)  Pour l’article homonyme, voir Isomorphisme.  forstérite Sommaire …   Wikipédia en Français

  • Substitution isomorphique — Isomorphisme (chimie)  Pour l’article homonyme, voir Isomorphisme.  forstérite Sommaire …   Wikipédia en Français

Share the article and excerpts

Direct link
… Do a right-click on the link above
and select “Copy Link”