324 



METALS. 



Before the blowpipe it fuses easily and affords a globule 

 which becomes angular on cooling. Dissolves in nitric acid, 

 from which it is precipitated by putting in a clean piece of 

 copper. 



Dif. Distinguished by being malleable ; from bismuth 

 and other white native metals by affording no fumes before 

 the blowpipe ; by affording a solution with vm^&> acid, 

 which becomes black on exposure. ^fa&7\x t-~ 



Obs. Native silver occurs in masses and string-like ar 

 borescences, penetrating rocks, and is found in igneous rock 

 and in sedimentary strata, in the vicinity of dikes of trap 

 and porphyry. 



The mines of Norway, at Kongsberg, formerly afforded 

 magnificent specimen^ of native silver, but they are now 

 mostly under water. One specimen from this locality, at 

 Copenhagen, weighs five hundred pounds. Other European 

 localities are in Saxony, Bohemia, the Hartz, Hungary, 

 Dauphiny. Peru and Mexico also afford native silver. A 

 Mexican specimen from Batopilas, weighed when obtained, 

 400 pounds ; and one from Southern Peru, (mines of Huan- 

 tajaya,) weighed over 8 c Vt. / In the United States, elegant 

 specimens are associated with the native copper of Lake Su- 

 perior. The silver generally penetrates the copper in masses 

 and strings, and is very nearly pure, notwithstanding the 

 copper about it. 



Much of the galena of the west contains a very small pel 

 centage of silver, and that of Monroe, Conn., yields nearly 3 

 per cent. 



Native silver has also been observed near the Sing Sing 

 state prison ; at the Bridgewater copper mines, N. J. ; and 

 in handsome specimens at King's mine, Davidson county, 

 North Carolina. 

 f^ Uses, The uses of silver are, for the manufacture of va- 

 rious articles of luxury, for plating other metals, for philo- 

 sophical instruments, for coinage, and also various purposes 

 in the arts. For coins, it is alloyed in this country with 

 copper, and is thus rendered harder and more durable ; 1000 

 J>arts of the coin contains 100 parts of copper, j When thi 

 alloy is boiled with a solution of cream of tartar and sea 

 salt, or scrubbed with water of ammonia, the superficia. 



How is native silver distinguished ? How does it occur and in wha 

 rocks 1 Where does silver occur in the U. States, and how 1 Wha 



are the uses of silve 



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