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Howieite Mineral Data
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General Howieite Information
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 Chemical Formula: |
Na(Fe++,Mn++)10(Fe,Al)2Si12O31(OH)13 |
| Composition: |
Molecular Weight = 2,544.93 gm |
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Sodium 0.90 % Na 1.22 % Na2O |
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Magnesium 0.48 % Mg 0.79 % MgO |
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Manganese 6.48 % Mn 8.36 % MnO |
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Aluminum 0.64 % Al 1.20 % Al2O3 |
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Iron 17.56 % Fe 18.07 % FeO / 5.02 % Fe2O3 |
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Silicon 26.49 % Si 56.66 % SiO2 |
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Hydrogen 0.50 % H 4.50 % H2O |
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Oxygen 46.96 % O |
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______ ______ |
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100.00 % 95.82 % = TOTAL OXIDE |
| Empirical Formula: |
NaFe2+6.4Mn2+3Mg0.5Fe3+1.6Al0.62(Si12)2(O31)(OH)12.7 |
| Environment: |
In the Jurassic-aged Franciscan Formation metamorphosed to blue-shist facies (high pressure, low temperature ). |
| IMA Status: |
Approved IMA 1964 |
| Locality: |
Laytonville quarry, 5 miles south of Laytonville, Mendocino Co. California. Link to MinDat.org Location Data. |
| Name Origin: |
Named for Robert Andrew Howie (1923-), British mineralogist and petrologist, King's College, London University, UK. |
| Name Pronunciation: |
Howieite  |
| Synonym: |
ICSD 6257 |
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PDF 19-571 |
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