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	 Melanothallite Mineral Data  |  |  | 
   
| General Melanothallite  Information  | 
|  Chemical  Formula: | Cu2OCl2 | 
|  Composition: | Molecular Weight = 214.00 gm | 
|  | Copper    59.39 %  Cu   74.34 % CuO | 
|  | Chlorine  33.13 %  Cl   33.13 % Cl | 
|  | -   %
  Cl   -7.48 % -O=Cl2 | 
|  | Oxygen     7.48 %  O | 
|  | ______        ______ | 
|  | 100.00 %      100.00 % = TOTAL OXIDE | 
|  Empirical Formula: | Cu2OCl2 | 
|  Environment: | Sublimed on crater walls formed in 1868 and 1906. | 
|  IMA Status: | Valid Species (Pre-IMA) 1870 | 
|  Locality: | Vesuvius, Campania, Italy. Link to MinDat.org Location Data. | 
|  Name Origin: | Named from the Greek for black and a young shoot, for the mineral�s property of turning green on exposure. | 
|  Name Pronunciation: | Melanothallite  + Pronunciation   | 
|  Synonym: | ICSD 1055 | 
|  | PDF 35-679 | 
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