Thorasphite

Th2H(AsO4)2(PO4) · 6H2O
IMA status
  • Approved
IMA symbol
Tp
IMA approved
2017
Also known as
  • IMA2017-085
  • Thorasphiet

Where it forms, where it's found

Geological setting

tin deposit

Type locality
Elsmore Tin Mine (Elsmore Tin lodes)
  1. Elsmore
  2. Gough Co.
  3. New South Wales
  4. Australia

-29.8106°, 151.2867°

1recorded occurrences
Source · OpenStreetMap

Radioactivity

Physical

Colour
brownish pink to salmon pink
Streak
white
Density
4.185 g/cm³

Crystallography

Crystal system
Orthorhombic
Space group
Pbcn
Cell parameters
a = 13.673(3) Å · b = 9.925(2) Å · c = 10.222(2) Å
Ratio a:b:c
1 : 0.726 : 0.748
Z
4
Type-locality form

prismatic to acicular crystals up to 0.08 mm in length and 0.002 mm across

Chemical composition

Constituent elements
Mass composition breakdown
ElementAtoms At. mass g/mol Mass g/molMass share
90ThThoriumThorium2232.038464.076
49.06%
8OOxygenOxygen1815.999287.982
30.44%
33AsArsenicArsenic274.922149.844
15.84%
15PPhosphorusPhosphorus130.97430.974
3.27%
1HHydrogenHydrogen131.00813.104
1.39%
Total945.980100.00%

Mass share = atoms × atomic mass ÷ molar mass × 100

From IMA formula

Synonyms

  • IMA2017-085
  • Thorasphiet

In other languages

German
Thorasphit

Classification

Strunz
10th ed.

8.CD.40

  • 8Phosphates, Arsenates, VanadatesClass
  • 8.CPhosphates without additional anions, with H2ODivision
  • 8.CDWith only medium-sized cations, RO4:H2O = 1:2Group
  • 8.CD.40ThorasphiteSpecies

Literature, links & citation

Citations
  1. 2018Hålenius, U., Hatert, F., Pasero, M., Mills, S. J. (2018) IMA Commission on New Minerals, Nomenclature and Classification (CNMNC) Newsletter 41. European Journal of Mineralogy, 30. 183-186 doi:10.1127/ejm/2018/0030-2736DOI: 10.1127/ejm/2018/0030-2736
  2. 2022(2022) Thorasphite. Handbook of Mineralogy. Mineralogical Society of America
  3. 2022Elliott, Peter (2022) Thorasphite, Th2H(AsO4)2(PO4)·6H2O, a New Mineral from Elsmore, New South Wales, Australia. The Canadian Mineralogist, 60 (4) 719-727 doi:10.3749/canmin.2100064DOI: 10.3749/canmin.2100064
Cite this entry
@misc{mineral2026,
  author    = {Mineral Index editorial board},
  title     = {Thorasphite — Mineral Index},
  year      = {2026},
  url       = {https://mineralindex.org/minerals/thorasphite-52750},
  note      = {Accessed 2026-05-11}
}