yb A. LIVERSIDGE. 



decrepitates, then fuses and spreads much, gives off a little water 

 and yields a slight sublimate. On charcoal before the blow pipe, 

 it fuses, yields white fumes and incrustation, a bright green flame 

 and globules composed of copper and lead. Soluble in nitric acid. 



MM. Mallard and Cumenge (C.R. 113, 519, Oct. 26, 1891) 

 found both cubic and octahedral crystals, the former sometimes 

 2 cm. in diameter or nearly three times the size of the Broken 

 Hill crystals. They regard the octahedral crystals as tetragonal, 

 so that if this be confirmed, the mineral is dimorphous. 



Nantokite. 



Some specimens of this rare mineral were forwarded to me for 

 identification, on December 22nd, 1893, by Mr. J. R. McKay, 

 manager of the Broken Hill South Silver Mining Company, N. S. 

 Wales. To save time, as this Society did not then meet for the 

 reading of papers for nearly six months, I sent an account of the 

 nantokite to the Mineralogical Society of Great Britain and 

 Ireland which was read at their meeting in April last. Mr. 

 McKay also sent me a report upon the mineral by Mr. J. 0. 

 Armstrong of the above mine, and Mr. A. D. Carmichael of the 

 Broken Hill Proprietary Block 10 Mine, as follows : — 



" Mineral found at the Broken Hill South Mine, at the three 

 hundred feet level in the carbonate of lead stopes, below original 

 water level. It was found in one boulder about f foot diameter ; 

 the boulder consists principally of carbonate of lead, native and 

 oxide of copper, with films of oxychloride of copper. The crystals 

 on examination, were found to consist wholly of copper and 

 chlorine, a quantitative analysis showing : — 



Copper 64-28 



Chlorine ... 35-92 



100-20 



This corresponds extremely closely to the calculated percentage 

 composition of cuprous chloride, Cu 2 Cl 2 which is — 





