MINERALOGY. 469 



Germany, and most abundantly in North America ; but 

 no known locality in the world exceeds in the abundance 

 of native copper the Lake Superior region, where it 

 occurs mostly in vertical seams in trap and masses of 

 sandstone. A large bowlder, weighing 3704 pounds, 

 taken from thence is now at Washington, and another 

 from the same vicinity, weighing 137 pounds, has been 

 many years in the Yale College collections. H. = 2.5 

 to 3.0. Gr. = 8.3 to 9.0. Chemical sign $ . 



Native Lead. Lead rarely occurs pure, but when 

 met with, shows itself thread-like, in thin laminse or 

 globules, coarse or fine granular. Color lead-gray; 

 opaque ; ductile, malleable ; fuses easily ; dissolves in 

 nitric acid, but precipitates in sulphuric acid. H. = 

 1.0 to 2.0. G. = 11. This species, of doubtful exist- 

 ence and very rare, is said to be met with at Alston- 

 moor, England, in lava in Madeira, in the mines of Car- 

 thagena, Murcia, in carboniferous limestone, Bristol, 

 and at Kenmore, Ireland. Chemical sign h. 



Native Mercury or Quicksilver exists in a native 

 state, but occurs mostly as a sulphuret (cinnabar), in 

 small fluid globules or drops scattered along the gan- 

 gue.* Luster, strongly shining metallic : color, tin- 

 white; opaque. Freezes at 32 E., boils at 280 R., 

 vaporizes at all degrees of heat ; dissolves readily in 

 nitric acid. The common name of quicksilver is a trans- 

 lation of the old name for mercury, argentum vivum. 

 G. 13.5 to 13.6. Found always associated with cin- 

 nabar. Chemical sign $ . 



* The rock immediately enveloping the ore is called the Gangue. 

 A vein often consists for the most part of the rock material called 

 the Gangue. The usual gangue in metallic veins is either quartz, 

 calc-spar, or heavy spar ; less frequently fluor spar. DANA. 



