Mindat Logo
Home Page Log In Message Board The Mindat Directory
Register Search Pages Chat Now! (3 online) Mindat Auctions

Brownmillerite

Big Photo

Caspar quarry, Ettringer Bellerberg Mt. (Bellberg Mt.; Bellenberg Mt.; Billenberg Mt.; Boilenberg Mt.), Bellerberg volcano, Ettringen, Mayen, Eifel Mts, Rhineland-Palatinate, Germany
© 2008 Jesse Crawford

Show Brownmillerite Photos (3)
Formula:
Ca
 
2
(Al,Fe
3+
 
)
 
2
O
 
5
System:Orthorhombic
Name:The artificial compound was named in 1932 for Dr. Lorrin Thomas Brownmiller (1902-1990), Chief Chemist of the Alpha Portland Cement Company, Easton, Pennsylvania, USA. The name was then transferred to the naturally-occurring mineral.
This page provides mineralogical data about Brownmillerite.

Classification of Brownmillerite

IMA status:Approved
Strunz 8th edition ID:4/A.07-10
Nickel-Strunz 10th (pending) edition ID:4.AC.10

4 : OXIDES (Hydroxides, V[5,6] vanadates, arsenites, antimonites, bismuthites, sulfites, selenites, tellurites, iodates)
A : Metal: Oxygen = 2:1 and 1:1
C : M:O = 1:1 (and up to 1:1.25); with large cations (+- smaller ones)
Dana 8th edition ID:7.11.2.1

7 : MULTIPLE OXIDES
11 : Miscellaneous
Hey's CIM Ref.:7.20.15

7 : Oxides and Hydroxides
20 : Oxides of Fe
mindat.org URL:http://www.mindat.org/min-790.html
Please feel free to link to this page.

Type Occurrence of Brownmillerite

Co-type Localities:Mayener Feld, Southern lava flow, Bellerberg volcano, Ettringen, Mayen, Eifel Mts, Rhineland-Palatinate, Germany
Ettringer Feld, Western lava flow, Bellerberg volcano, Ettringen, Mayen, Eifel Mts, Rhineland-Palatinate, Germany
Place of Conservation of Type Material:Mineral Museum, University of Cologne, Cologne, Germany (No. M5026/86)
National Museum of Natural History, Washington, D.C., USA (No. 120045)
Year of Discovery:1964
Geological Setting of type material:In thermally metamorphosed limestone blocks included in volcanic rocks
Associated Minerals at type locality:
WollastoniteSpinelPyrrhotitePortlanditeMayenite
LarniteJenniteJasmunditeGrossularGehlenite
EttringiteDiopsideCalciteAfwillite

Occurrences of Brownmillerite

Geological Setting:In thermally metamorphosed limestones

Crystallography of Brownmillerite

Crystal System:Orthorhombic
Cell Parameters:a = 5.57Å, b = 14.52Å, c = 5.34Å
Ratio:a:b:c = 0.384 : 1 : 0.368
Unit Cell Volume:V 431.88 ų (Calculated from Unit Cell)

Optical Data of Brownmillerite

Type:Biaxial (-)
RI values: nα = 1.960 nβ = 2.010 nγ = 2.040
2V:Measured: 75° , Calculated: 72°
Maximum Birefringence:δ = 0.080

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

Chemical Properties of Brownmillerite

Formula:
Ca
 
2
(Al,Fe
3+
 
)
 
2
O
 
5
Essential elements:Al, Ca, O
All elements listed in formula:Al, Ca, Fe, O

Relationship of Brownmillerite to other Species

Related Minerals - Nickel-Strunz Grouping):

- +
4.AC.05Swedenborgite
NaBe
 
4
SbO
 
7
4.AC.10Srebrodolskite
Ca
 
2
Fe
 
2
O
 
5
4.AC.15Montroydite
HgO
4.AC.20Litharge
PbO
4.AC.20Romarchite
SnO
4.AC.25Massicot
PbO
Related Minerals - Hey's Index Grouping:

- +
7.20.1Wüstite
FeO
7.20.2Magnetite
Fe
2+
 
Fe
3+
2
O
 
4
7.20.3Maghemite
Fe
 
2
O
 
3
7.20.4Hematite
Fe
 
2
O
 
3
7.20.5Goethite
α-Fe
3+
 
O(OH)
7.20.6Akaganeite
β-Fe
3+
 
O(OH,Cl)
7.20.7Feroxyhyte
Fe
3+
 
O(OH)
7.20.8Lepidocrocite
γ-Fe
3+
 
O(OH)
7.20.9Ferrihydrite
Fe
 
5
O
 
3
(OH)
 
9
7.20.10Amakinite
(Fe
2+
 
,Mg)(OH)
 
2
7.20.11Magnesioferrite
MgFe
3+
2
O
 
4
7.20.12Muskoxite
Mg
 
7
Fe
 
4
O
 
13
·10H
 
2
O
7.20.13Srebrodolskite
Ca
 
2
Fe
 
2
O
 
5
7.20.14Hercynite
FeAl
 
2
O
 
4

Other Names for Brownmillerite

Synonyms:
CeliteIMA1963-017
Other Languages:
German:Brownmillerit
Celit
Russian:Браунмиллерит
Spanish:Brownmillerita
Celita

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 Brownmillerite

Reference List:Hentschel, G., (1964): Mayenit, 12CaO 7Al2O3, und Brownmillerit, 2CaO.(Al,Fe)2O3, zwei neue Minerale in den Kalksteineinschlüssen der Lava des Ettringer Bellerberges: Neues Jahrb. Mineral., Mh. 1964, 22-29.

American Mineralogist: 50: 2106.

Acta Crystallographica: B27: 2311-2315.

Internet Links for Brownmillerite

Search Engines:
  • Look for Brownmillerite on Google
  • Look for Brownmillerite images on Google
    • External Links:
  • Look for Brownmillerite on Webmineral
  • Look for Brownmillerite on Athena Mineralogy
  • Look for Brownmillerite on Wikipedia
  • Look for Brownmillerite on Mineralien Atlas
  • Raman and XRD data at RRUFF project
  • American Mineralogist Crystal Structure Database
  • Search for Brownmillerite in the Natural History Museum (London) online catalogue
  • Brownmillerite details from Handbook of Mineralogy (PDF)
    • Mineral Dealers:
  • Search for - Brownmillerite - on e-Rocks Mineral Sales & Auctions
  • Rare and Unusual minerals at Mineralogical Research Company
  • rare and unusual minerals mainly crystallized
  • Mineral Classics - Worldwide Collector Quality Minerals and Gems
  • Buy minerals from Mineralium.com
  • Buy fine minerals and gemstones from Pala International
  • DAKOTA MATRIX offers Cabinet and Rare Species from Worldwide Localities.
  • Lapis Mineral Magazin
  • Find Brownmillerite on www.crystalclassics.co.uk
  • The Arkenstone - Fine Minerals
  • Buy Fine Minerals from mineralsweb.com
  • Wendel Minerals - Auktion & Shop
    • Jobs:
  • Mining & Geology Jobs

    • Page Sponsor

    Sponsorship:This page is currently not sponsored. Click here to sponsor this page.

    Localities for Brownmillerite

    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.
    (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.
    Austria
     
    • Styria
      • Bad Radkersburg
        • Klöch
    		R. Exel: Die Mineralien und Erzlagerstätten Österreichs (1993); Postl, W. et al. (2008)
    China
     
    • Xinjiang (Xinjiang-Uygur) Autonomous Region
      • Hami (Kumul; Qumul) Prefecture
        • Hami (Kumul; Qumul) Co.
          • Huangshan-Jing'erquan ore belt
    		Jingwen Mao, Pirajno, F., Zuoheng Zang, Fengmei Chai, Hua Wu, Shiping Chen, Linsong Cheng, Jianmin Yang, and Changqing Zhang (2007): Journal of Asian Earth Sciences (in press).
    Germany
     
    • Rhineland-Palatinate
      • Eifel Mts
        • Daun
          • Üdersdorf
    		Schüller, W., Betz, V., Die Mineralien vom Emmelberg, Lapis 12/1986
        • Mayen
          • Ettringen
            • Bellerberg volcano
              • Ettringer Bellerberg Mt. (Bellberg Mt.; Bellenberg Mt.; Billenberg Mt.; Boilenberg Mt.)
    		Hentschel, G. (1978): Seltene Minerale in Calcium-reichen Auswürflingen vom Bellerberg bei Mayen/Eifel, Aufschluß 29, 77-83
              • Southern lava flow
    		Hentschel, G. (1964): Mayenit, 12CaO . 7 Al2O3, und Brownmillerit, 2CaO.(Al,Fe)2O3, zwei neue Minerale in den Kalksteineinschlüssen der Lava des Ettringer Bellerberges, Neues Jahrbuch Mineralogie, Monatshefte, 22-29
              • Western lava flow
    		Hentschel, G. (1964): Mayenit, 12CaO . 7 Al2O3, und Brownmillerit, 2CaO.(Al,Fe)2O3, zwei neue Minerale in den Kalksteineinschlüssen der Lava des Ettringer Bellerberges, Neues Jahrbuch Mineralogie, Monatshefte, 22-29
    Israel
     
    • Negev desert
    		Gross, S. (1977): The Mineralogy of the Hatrurim Formation, Israel. Geological Survey of Israel, Bulletin no. 70, 80 pp.
    Mineral and/or Locality
    Google
     
    www.mindat.org Web
    Copyright © Jolyon Ralph and Ida Chau 1993-2009. 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. Current server date and time: 6th Nov 2009 04:11:24