Kushiroite

CaAlAlSiO6
IMA status
  • Approved
IMA symbol
Ks
IMA approved
2008
Also known as
  • IMA2008-059
  • Kushiroiet
  • UM2005-27-SiO:AlCa

Where it forms, where it's found

Geological setting

Carbonaceous chondrite meteorite.

Type locality
Allan Hills 85085 meteorite
  1. Allan Hills
  2. Victoria Land
  3. East Antarctica
  4. Antarctica

-76.8483°, 156.4203°

8recorded occurrences
Source · OpenStreetMap

Crystallography

Crystal system
Monoclinic
Space group
#10
Cell parameters
a = 9.609(3) Å · b = 8.652(2) Å · c = 5.274(2) Å
Cell angles
β = 106.06(2) °
Ratio a:b:c
1 : 0.900 : 0.549
Type-locality form

Grains, along with another pyroxene, forming a mantle (maximum width of ~6 μm) on a grossite grain. The largest kushiroite grain is 9 μm long.

Crystal structure

Chemical composition

Constituent elements
Mass composition breakdown
ElementAtoms At. mass g/mol Mass g/molMass share
8OOxygenOxygen615.99995.994
44.01%
13AlAluminiumAluminium226.98253.964
24.74%
20CaCalciumCalcium140.07840.078
18.37%
14SiSiliconSilicon128.08528.085
12.88%
Total218.121100.00%

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

From IMA formula

Synonyms

  • IMA2008-059
  • Kushiroiet
  • UM2005-27-SiO:AlCa

In other languages

German
IMA 2008-059 · Kushiroit
Italian
kushiroite
Japanese
久城石

Classification

Strunz
10th ed.

9.DA.15

  • 9SilicatesClass
  • 9.DInosilicatesDivision
  • 9.DAInosilicates with 2-periodic single chains, Si2O6; pyroxene familyGroup
  • 9.DA.15KushiroiteSpecies
Dana
8th ed.

65.01.03.08

  • 65Inosilicates Single-width, Unbranched Chains, (w=1)Class
  • 65.01Single-Width Unbranched Chains, W=1 with chains P=2Type
  • 65.01.03— unnamed intermediate level —Group
  • 65.01.03.08KushiroiteSpecies

Group, growth & confusion

In the same group
25 members

Literature, links & citation

Citations
  1. 2005Pascal, M.-L., Katona, I., Fonteilles, M., Verkaeren, J. (2005) Relics of high-temperature clinopyroxene on the join Di-CaTs with up to 72 mol% Ca(Al,Fe3+)AlSiO6 in the skarns of Ciclova and Magureaua Vaţei, Carpathians, Romania. The Canadian Mineralogist, 43 (3). 857-881 doi:10.2113/gscanmin.43.3.857 DOI: 10.2113/gscanmin.43.3.857
  2. 2009Ma, C., Simon, S. B., Rossman, G. R., Grossman, L. (2009) Calcium Tschermak's pyroxene, CaAlAlSiO6, from the Allende and Murray meteorites: EBSD and micro-Raman characterizations. American Mineralogist, 94 (10) 1483-1486 doi:10.2138/am.2009.3231DOI: 10.2138/am.2009.3231
  3. 2009Kimura, M., Mikouchi, T., Suzuki, A., Miyahara, M., Ohtani, E., Goresy, A. E. (2009) Kushiroite, CaAlAlSiO6: A new mineral of the pyroxene group from the ALH 85085 CH chondrite, and its genetic significance in refractory inclusions. American Mineralogist, 94 (10) 1479-1482 doi:10.2138/am.2009.3242DOI: 10.2138/am.2009.3242
  4. 2012Kruszewski, Ł., Ciesielczuk, J., Misz-Kennan, M. (2012): What have meteorites to do with coal fires? A case of Upper and Lower Silesian Coal Basins. Min. Spec. Pap.: 40: 28–29
  5. 2018Kruszewski, Ł., Gatel, P., Thiéry, V., Moszumańska, I., Kusy, D. (2018): Crystallochemical Behavior of Slag Minerals and the Occurrence of Potentially New Mineral Species from Lapanouse-de-Sévérac, France. Chapter 13, in: Stracher, G.B. (Ed.), Coal and Peat Fires: A Global Perspective, Vol. 5 – “Case Studies – Advances in Field and Laboratory Research”, 241–300.
Cite this entry
@misc{mineral2026,
  author    = {Mineral Index editorial board},
  title     = {Kushiroite — Mineral Index},
  year      = {2026},
  url       = {https://mineralindex.org/minerals/kushiroite-39329},
  note      = {Accessed 2026-05-11}
}