Mindat Logo
Home Page Log In Message Board The Mindat Directory
Register Search Pages Chat Now! (2 online) Mindat Auctions

Kosmochlor

Big Photo

Tawmaw (Tawhmaw; Taw Maw), Myitkyina-Mogaung District, Kachin State, Burma (Myanmar)
© Knut Eldjarn

Show Kosmochlor Photos (2)
Formula:
NaCr[Si
 
2
O
 
6
]
System:MonoclinicColour:emerald green
Hardness:6


Pyroxene Group - Clinopyroxene Subgroup.

Classification of Kosmochlor

IMA status:Approved
Strunz 8th edition ID:8/F.01-170
Nickel-Strunz 10th (pending) edition ID:9.DA.25

9 : SILICATES (Germanates)
D : Inosilicates
A : Inosilicates with 2-periodic single chains, Si2O6; pyroxene family
Dana 8th edition ID:65.1.3c.4

65 : INOSILICATES Single-Width,Unbranched Chains,(W=1)
1 : Single-Width Unbranched Chains, W=1 with chains P=2
Hey's CIM Ref.:14.15.1

14 : Silicates not Containing Aluminum
15 : Silicates of Cr
mindat.org URL:http://www.mindat.org/min-2258.html
Please feel free to link to this page.

Type Occurrence of Kosmochlor

Type Locality:Coahuila meteorite, Bolsom de Mapimí, Coahuila, Mexico
Year of Discovery:1897

Physical Properties of Kosmochlor

Colour:emerald green
Streak:pale green
Hardness (Mohs):6
Cleavage:Distinct/Good

Crystallography of Kosmochlor

Crystal System:Monoclinic
Cell Parameters:a = 9.57Å, b = 8.71Å, c = 5.26Å
β = 107.49°
Ratio:a:b:c = 1.099 : 1 : 0.604
Unit Cell Volume:V 418.18 ų (Calculated from Unit Cell)

Optical Data of Kosmochlor

Type:Biaxial
RI values: nα = 1.766 nγ = 1.781
Maximum Birefringence:δ = 0.015

Chart shows birefringence interference colour range (at 30µm thickness) and does not take into account mineral colouration.
Surface Relief:Moderate
Dispersion:strong

Chemical Properties of Kosmochlor

Formula:
NaCr[Si
 
2
O
 
6
]
Essential elements:Cr, Na, O, Si
All elements listed in formula:Cr, Na, O, Si
Common Impurities:Ti,Al,Fe,Mn,Mg,Ca,K,P

Relationship of Kosmochlor to other Species

Related Minerals - Nickel-Strunz Grouping):
9.DA.05Donpeacorite
(Mn
2+
 
,Mg)Mg[SiO
 
3
]
 
2
9.DA.05Enstatite
Mg
 
2
[SiO
 
3
]
 
2
9.DA.05Ferrosilite
Fe
 
2
[SiO
 
3
]
 
2
9.DA.05Akimotoite
(Mg,Fe
2+
 
)SiO
 
3
9.DA.10Clinoenstatite
Mg
 
2
[Si
 
2
O
 
6
]
9.DA.10Clinoferrosilite
Fe
2+
 
(Fe
2+
 
,Mg)[Si
 
2
O
 
6
]
9.DA.10Kanoite
Mn
2+
 
(Mg,Mn
2+
 
)[Si
 
2
O
 
6
]
9.DA.10Pigeonite
(Mg,Fe
2+
 
,Ca)(Mg,Fe
2+
 
)[Si
 
2
O
 
6
]
9.DA.15Augite
(Ca,Na)(Mg,Fe
2+
 
,Al,Fe
3+
 
,Ti)[(Si,Al)
 
2
O
 
6
]
9.DA.15Diopside
CaMg[Si
 
2
O
 
6
]
9.DA.15Esseneite
CaFe
3+
 
[AlSiO
 
6
]
9.DA.15Hedenbergite
CaFe
2+
 
[Si
 
2
O
 
6
]
9.DA.15Johannsenite
CaMn
2+
 
[Si
 
2
O
 
6
]
9.DA.15Petedunnite
Ca(Zn,Mn
2+
 
,Mg,Fe
2+
 
)[Si
 
2
O
 
6
]
9.DA.20Aegirine-augite
(Na,Ca)(Fe,Fe,Mg,Al)Si
 
2
O
 
6
9.DA.20Omphacite
(Ca,Na)(Mg,Al)[Si
 
2
O
 
6
]
9.DA.25Aegirine
NaFe
3+
 
[Si
 
2
O
 
6
]
9.DA.25Jadeite
Na(Al,Fe
3+
 
)[Si
 
2
O
 
6
]
9.DA.25Jervisite
(Na,Ca,Fe
2+
 
)(Sc,Mg,Fe
2+
 
)[Si
 
2
O
 
6
]
9.DA.25Namansilite
NaMn
3+
 
[Si
 
2
O
 
6
]
9.DA.25Natalyite
Na(V
3+
 
,Cr)[Si
 
2
O
 
6
]
9.DA.30Spodumene
LiAl[Si
 
2
O
 
6
]
Related Minerals - Hey's Index Grouping:
14.15.2Natalyite
Na(V
3+
 
,Cr)[Si
 
2
O
 
6
]
14.15.3Knorringite
Mg
 
3
Cr
 
2
[SiO
 
4
]
 
3
14.15.4Krinovite
Na
 
2
Mg
 
4
Cr
3+
2
[O
 
2
|Si
 
6
O
 
18
]
14.15.5Uvarovite
Ca
 
3
Cr
 
2
[SiO
 
4
]
 
3

Other Names for Kosmochlor

Synonyms:
Chrome-AcmiteCosmochloreIMA1965-007Ureyite
Italian names:
Cloromelanitite
Russian names:
Космохлор

Other Information

Health Warning:No information on health risks for this material has been entered into the database. You should always treat mineral specimens with care.

References for Kosmochlor

Reference List:American Mineralogist (1965): 50: 2096.

American Mineralogist (1968): 53: 511.

Clark, J.R., D.E. Appleman, and J.J. Papike (1969) Crystal-chemical characterization of clinopyroxenes based on eight new structure refinements. MSA Special Paper 2: 31-50.

Cameron, M., S. Shigeho, C.T. Prewitt & J.J. Papike (1973), High temperature crystal chemistry of acmite, diopside, hedenbergite, jadeite, spodumene and ureyite: American Mineralogist: 58: 594-618.

Mineralogical Magazine (1988): 52: 535.

Origlieri, M.J., Downs, R.T., Thompson, R.M., Pommier, C.J.S., Denton, M.B., and harlow, G.E. (2003) High-pressure crystal structure of kosmochlor, NaCrSi2O6 and systematics of anisotropic compression in pyroxenes. American Mineralogist: 88: 1025-1032.

Internet Links for Kosmochlor

Search Engines:
  • Look for Kosmochlor on Google
  • Look for Kosmochlor images on Google
    • External Links:
  • Look for Kosmochlor on Webmineral
  • Look for Kosmochlor on Athena Mineralogy
  • Look for Kosmochlor on Wikipedia
  • Look for Kosmochlor on Mineralien Atlas
  • Raman and XRD data at RRUFF project
  • American Mineralogist Crystal Structure Database
  • Search for Kosmochlor in the Natural History Museum (London) online catalogue
  • Kosmochlor details from Handbook of Mineralogy (PDF)
    • Mineral Dealers:
  • Search for Kosmochlor on minvision.com
  • Wright's Rock Shop - excellent mineral specimens since 1970
  • Find Kosmochlor on www.crystalclassics.co.uk
  • Search for Kosmochlor at Thames Valley Minerals
  • Buy fine minerals and gemstones from Pala International
  • Wendel Minerals - Auktion & Shop
  • Mineral Classics - Worldwide Collector Quality Minerals and Gems
  • Top quality minerals from Kristalle of California
  • Lapis Mineral Magazin
  • Buy Fine Minerals from mineralsweb.com
  • e-Rocks - Mineral Auctions and Sales
  • Fabre Minerals - search for Kosmochlor specimens
    • Jobs:
  • Mining & Geology Jobs

    • Page Sponsor

    Sponsorship:This page is currently not sponsored. Click here to find out how you can sponsor this page.

    Localities for Kosmochlor

    Hide Locality List
    The map shows a selection of localities that have latitude and longitude coordinates recorded. Click on the symbol to view information about a locality. The symbol next to localities in the list can be used to jump to that position on the map.
    These maps work faster with Firefox!
    (TL) indicates type locality. ? indicates mineral may be doubtful at this locality. All other localities listed without reference should be considered as uncertain and unproven until references can be found.
    Burma (Myanmar)
     
    • Kachin State
      • Myitkyina-Mogaung District
    Italy
     
    • Piedmont
      • Torino Province
        • Susa Valley
          • Condove
    		Fornaseri M., Bensa G. (1939): Sulla cloromelanitite di Mocchie in Val di Susa. Periodico di Mineralogia - Roma pp. 217-230.
    Japan
     
    • Honshu Island
      • Chubu Region
        • Niigata Prefecture
    		wwwsoc.nii.ac.jp/jampeg/93-11.htm.
    Fossa Magna Museum specimen, Itoigawa
      • Chugoku region
        • Okayama prefecture
          • Ohsa-cho
    Mexico
     
    • Coahuila
      • Bolsom de Mapimí
    USA
     
    • Arizona
      • Coconino Co.
        • Meteor Crater and vicinity
    		Anthony, J.W., et al (1995), Mineralogy of Arizona, 3rd.ed.: 171-172, 269, 354; Olsen, E. & L. Fuchs (1968), Krinovite, NaMg2CrSi3O10 = a new meteorite mineral, Science 161: 786-787.
    Mineral and/or Locality
    Google
     
    www.mindat.org Web
    Copyright © Jolyon & Ida Ralph 1993-2008. Site Map. Locality, mineral & photograph data are the copyright of the individuals who submitted them.Further information contact the Site hosted & developed by Jolyon Ralph. Mindat.org is an online information resource dedicated to providing free mineralogical information to all. Mindat relies on the contributions of hundreds of members and supporters. If you would like to add information to improve the quality of our database, then click here to register.