276 Kunz — Native Antimony from New Brunswick. 



of Professor G. I. Chase and Wm. Petherick, M. E., in their 

 prospectus of the Brunswick Mining Co.* It is mentioned 

 however in the fifth edition of J. D. Dana's System of Mineral- 

 ogy, page 18, as of rare occurrence at the Prince William 

 mine. The mining then was all merely on the surface, but 

 •within the last two years it has been carried on to a considera- 

 ble depth. At a depth of from 100 to 150 feet the native 

 antimony is occasionally found in large pockets, some of which 

 contain fully one ton of the pure mineral ; it is associated with 

 stibnite, valentinite and kermesite. 



In its most common form the mineral is very compact, and 

 at times finely granular, in appearance, resembling very closely 

 the native antimony of South Ham, Canada ; in this form it 

 breaks at times with a slightly conchoidal fracture and has a 

 decided steel-blue color. The forms in which it occurs are 

 usually either rounded or elongated masses, from ten to twelve 

 inches across, and weighing from 20 to 50 lbs. ; it passes into 

 a coarse granular variety where it very closely resembles the 

 mineral from Sarawak, Borneo. The most remarkable form, 

 however, is that where it occurs in radiated masses of crystalline 

 plates. The single blades are from one to two and occasionally 

 four inches in length and |-th of an inch across, being nearly 

 as large as those of the artificial metal of commerce. The 

 radiations seem to have massed around a common center, as if 

 the mineral had cooled or crystallized slowly from without. 

 One fine mass of this radiated tin-white metal measured over 

 six inches across. Yery small microscopic crystals about 

 .05 mm. in size were developed by removing the calcite with 

 acid, and mention was made of some large ones that had been 

 observed, but these had been lost. Some of the crystalline 

 cleavages have striations similar to those described by Las- 

 peyresf that are also observed on the artificial antimony, and 

 on the coarsely grained native variety from AUemont; these 

 he refers to a polysynthetic twinning with 24i2 as the twin- 

 ning-plane. The specific gravity of a pure piece of the coarsely 

 crystalline bladed mineral was found to be 6*606 at 15°, and of 

 the very compact, finely granular mineral 6'693. The follow- 

 ing chemical results were obtained by Mr. James B. Mackin- 

 tosh, E. M., School of Mines, New York City. 



Coarse grained variety. 



Gangue # 84 per cent. 



Iron 0-11 " 



Arsenic... 0-86 " 



* Reports of Professor George I. Chase and Wm. Petherick, M. B., to the Bruns- 

 wick Antimony Co., Boston. 1864. 



t Zeitsch. deutsch. geol. G-es., 1875, p. 574. 



