312 Schaller — Identity of Stelznerile with Antlerite. 



Cnlcnlated Calculated 



Autlerite Stelzuerite 3CuO.lSO3.aHaO lOCuO.^SOs.THaO 



12 3 4 5 6 



CnO ... 68-10 (>7-64 07-08 64-01 67-2-' 68-45 



SO, 20-46 21-49 22-40 22-19 2261 20-69 



H.,6 11-11 10-76 10-22 10-37 10-17 10-86 



ZiiO ... 0-29 0-04 



CaO ... 0-05 0-04 0-06 0-57 



Fe^O^ .. 0-34 1-14 



Residue 0-44 1-42 



Moisture -33 



10010 99-97 100-54 100-03 100-00 lOO'OO 



with the simpler stelzuerite formula. As no certain differences 

 could be found in the optical properties and as the analyses 

 agree so closely with one another, the two minerals stelzuerite 

 and antlerite must be considered as identical. 



The characterization given stelzuerite is much more complete 

 than that of antlerite, and the formula deduced, CuSO^. 

 2Cu(OH)5, is also simpler and is doubtless the correct one for 

 the species. The name antlerite has, however, priority by ten 

 years, and is the one to be adopted. 



On careful investigation antlerite will doubtless be found to 

 be much more abundant than is now thought, and much of 

 what is now called brochantite may be found, on analysis, to be 

 the closely related antlerite. Thus the artificial brochantite, 

 described by Dana on page 926 of the System of Mineralogy, 

 is in reality antlerite. 



Chemical Laboratory, 



United States Geological Survey. 



