NO. 2351. NOTES ON METALLIC MINERALS— SHANNON. 597 



Analysis of boulangerite from Peru. 



Per cent. 



Insoluble : 0. 36 



Iron 0. 47 



Lead 54. 34 



Silver Trace. 



Antimony 25. 33 



Sulphur 18. 51 



Total 99. 01 



A slight evolution of carbon dioxide took place upon solution of 

 the mineral in hydrochloric acid, indicating that a small amount of 

 siderite was included in the sample as impurity. The iron may all 

 be in this form, and the 1 per cent loss is probably COg and MnO, 



BOULANGEBITE FROM OBEK-LAHU, GERMANY. 



A specimen of boulangerite in the United States National Museum 

 collections, labeled Ober-Lahr, Germany, was received in exchange 

 from Mr. B. Sturtz in 1886 (Cat. 47,005). The specimen is almost 

 entirel}^ composed of the boulangerite, the only impurities being rare 

 grains of buff manganiferous siderite and quartz. The boulangerite 

 is wholly devoid of any trace of fibrous structure, being completely 

 massive, with a schistose structure, somewhat rounded and contorted 

 and apparently due to pressure. The color is somewhat darker than 

 that of the fibrous boulangerites previously described, being com- 

 parable with that of some massive tetrahedrite. The mineral assumes 

 a bluish tarnish. The streak is the characteristic brownish color 

 typical of boulangerite. Upon analysis the material of this specimen 

 yielded the following results: 



Analysis of boulangerite from Ober-Lahr, Germany. 



Per cent. 

 Lead 54. 44 



Silver Trace. 



Antimony 24. 55 



Sulphur 18. 98 



Insoluble 1. 50 



Total 99. 47 



BOULANGEBITE FROM PRZIBRAM, BOHEMIA. 



A specimen in the United States National Museum collections 

 (Cat. 83,983) from Przibram looks precisely like the specimen from 

 Ober-Lahr. The color, structure and streak are the same. The 

 curved schistose structure is more pronounced, the platy layers curv- 

 ing completely around one end of the specimen. The boulangerite 

 contains considerable quartz and buff manganiferous siderite and 



