Trona

Trona
General
CategoryCarbonate mineral
Formula
(repeating unit)
Na2CO3·NaHCO3·2H2O
IMA symbolTn[1]
Strunz classification5.CB.15
Crystal systemMonoclinic
Crystal classPrismatic (2/m)
(same H-M symbol)
Space groupC2/c (no. 15)
Identification
ColorColorless (in transmitted light) or white, grey-white, also grey to yellowish grey, light yellow
Crystal habitColumnar, fibrous and massive.
Cleavage[100] perfect, [111] and [001] indistinct
FractureBrittle – subconchoidal
Mohs scale hardness2.5
LusterVitreous
StreakWhite
DiaphaneityTranslucent
Specific gravity2.11–2.17
Optical propertiesBiaxial (−)
Refractive indexnα = 1.412 nβ = 1.492 nγ = 1.540
Birefringenceδ = 0.128
SolubilitySoluble in water
Other characteristicsMay fluoresce under short wavelength ultraviolet
References[2][3][4][5]

Trona (trisodium hydrogendicarbonate dihydrate, also sodium sesquicarbonate dihydrate, Na2CO3·NaHCO3·2H2O) is a non-marine evaporite mineral.[4][6] It is mined as the primary source of sodium carbonate in the United States, where it has replaced the Solvay process used in most of the rest of the world for sodium carbonate production. Turkey is also a major producer.

  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. ^ Handbook of Mineralogy
  3. ^ Mindat
  4. ^ a b Webmineral data
  5. ^ Choi, C. S.; Mighell, A. D. (1 November 1982). "Neutron diffraction study of sodium sesquicarbonate dihydrate". Acta Crystallographica Section B: Structural Crystallography and Crystal Chemistry. 38 (11): 2874–2876. doi:10.1107/S0567740882010164.
  6. ^ Mineral galleries Archived 2005-04-08 at the Wayback Machine, 2008