178 



Miscellanies. 





occurs quite abundantly at Molieres, department of Gard, where it is 

 found in masses, whose fiacture exhibits a crystalline structure ; dis- 

 tinct crystals have not been obtained. It has a bluish gray color, 

 with a metallic lustre, and a specific gravity of 5.97. It is frequent- 

 ly covered in spots with hydrate of iron, and also a yellow substance, 

 which appears to be composed of the antimonic acid and the oxyd 

 of lead, and to have proceeded from the decomposition of the min- 

 eral. Its gangue is quartz and iron pyrites. 



It fuses readily under the blowpipe, with exhalations of sulphu- 

 rous acid and the white vapors of oxyd of antimony. On charcoal, 

 a yellow circle indicates the presence of lead. It is easily attacked 

 by nitric acid, and gives rise to an Antimonate or Antimonite of 

 Lead. Boiling, concentrated hydro-chloric acid dissolves it com- 

 pletely, with the extrication of sulphuretted hydrogen. 



Its composition is as follows: 



Sulphuret of antimony, - 

 Sulphuret of lead, 

 Sulphuret of iron, 

 Sulphuret of copper, 



35.0 

 62.1 



01.9 

 01.1 



100.1 



»M 



Neglecting the copper and iron, its formula is SbPb 3 



D 





25. Brevicite, 



M 



buch fur Min. Geog., tec, von Leonhard und Bronn, 3es H., 

 1835.) — This mineral was sent to Berzelius by M. Strom, from 

 Brevig in Norway, where it exists, filling the cavities of a trachytic 



rock 



It occurs in white 



lamellar radiated masses, with transparent prismatic crystals, usually 

 in the interior of the cavities. It is crossed by large bands of a deep 

 dirty red color. Its composition is as follows ; 



Silica, 



Alumina, 

 Sod ... _ 

 Lime, 

 Magnesia, 

 Water, 



Loss, 







43.88 



28.39 



10.32 



6.88 



0.21 



9.63 

 0.69 



100.00 



