Thortveitite

Last updated
Thortveitite
Thortveitite-ea14a.jpg
Thortveitite
General
Category Minerals
Formula (Sc,Y)2Si2O7
IMA symbol Tvt [1]
Strunz classification 9.BC.05
Crystal system Monoclinic
Crystal class Prismatic (2/m)
(same H-M symbol)
Space group C2/m
Identification
Mohs scale hardness5–6
Luster vitreous
Streak gray
Specific gravity 3.3–3.8

Thortveitite is a rare mineral consisting of scandium yttrium silicate (Sc,Y)2Si2O7. It is the most widespread scandium mineral, [2] but natural thortveitite is not widely exploited as a source of scandium metal. Most scandium is derived from mine tailings, which can include thortveitite. [3] Thortveitite mining in the United States ceased in 1969. [4]

Occurrence is in granitic pegmatites. It was named after Olaus Thortveit, a Norwegian engineer. It is grayish-green, black or gray in color. [5] [6] [7] [8]

A transparent gem quality example was found in 2004, and reported in The Journal of Gemmology. [9]

See also

References

  1. Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi: 10.1180/mgm.2021.43 . S2CID   235729616.
  2. "Scandium". Mindat.org . Retrieved 2025-05-29.
  3. Lowen, Eric. "Properties of Scandium". Stanford Advanced Materials. Retrieved Sep 24, 2024.
  4. Shelby Johnston. "Mineral Commodity Summaries 2025: Scandium" (PDF). National Minerals Information Center. U.S. Geological Survey. Retrieved 2025-05-29.
  5. "Thortveitite Mineral Data". webmineral.com. Retrieved 2021-05-03.
  6. "Thortveitite". www.mindat.org. Retrieved 2021-05-03.
  7. Bianchi, Riccardo; Pilati, Tullio; Diella, Valeria; Gramaccioli, Carlo Maria; Mannucci, Gregorio (1988-06-01). "A re-examination of thortveitite". American Mineralogist. 73 (5–6): 601–607. ISSN   0003-004X.
  8. Mineralien aus aller Welt. Walter Schumann. München. 1990. ISBN   978-3-405-14003-8. OCLC   610708490.{{cite book}}: CS1 maint: location missing publisher (link) CS1 maint: others (link)
  9. Chapman, R., Mercer, I.F., Rankin, A.H., Spratt, J. (2008). "Thortveitite – a new gemstone" (PDF). Journal of Gemmology. 31 (1): 1–6. Bibcode:2008JGem...31....1C. doi:10.15506/JoG.2008.31.1.1.{{cite journal}}: CS1 maint: multiple names: authors list (link)