MINERALOGY. 471 



ico. In the United States silver is disseminated through 

 much of the copper of Michigan. Also found in New 

 Jersey, and in King's Mine, North Carolina, Plate 32, 

 fig. 2. 



Native Gold occurs pure in cubes; crystals very 

 small; also in grains, laminae and masses, filiform, reti- 

 culated; also in arborescent tufts of moss-like shapes. 

 Often in flattened scales or plates, and in rolled masses 

 in gravel or sand detritus. Luster metallic. Color 

 varying from different shades of gold yellow to brassy 

 and silver-gray; opaque; ductile, malleable. Gold is 

 often rendered impure by being mixed with silver ; also 

 often contains copper and iron. H. = 2.5 to 3.0. G. 

 = 12.6 to 19.09. Chemical designation 0. Dissolves 

 in aqua regia, or a mixture of muriatic and nitric acids. 

 Gold is widely distributed all over the globe, although 

 seldom found in large masses. Mostly occurs in quartz, 

 pyrites (auriferous), brown iron-stone, feldspar, horn- 

 blende, stone, and in conglomerate and stratified transi- 

 tion rocks ; the detritus affording gold has proceeded 

 from the gold-bearing rocks. Occurs in the Ural Moun- 

 tains, Peru, Mexico, New Spain, California, Brazil ; 

 also in Hungary, Siebengebirgen, Saltzburg, Graub- 

 unden ; and in very small quantities in Bohemia, Hartz, 

 and Tyrol. The 1 Russian mines are said to be, at pres- 

 ent, the most productive in the world. Considerable 

 quantities of gold sand or gold dust is obtained from the 

 alluvial washings of the large rivers of South America 

 called wash gold. The sands of the Rhine, Rhone, 

 Danube, Isar, Moselle, and other rivers in Germany 

 contain gold in small quantities ; of these the Rhine has 

 been the most productive; at present only $9,000 are 

 extracted annually. The whole amount of gold in the 



