GOLD. 



317 



rivers, rather high up among the mountains ; and not only 

 along the streams where the torrents perform annually the 

 washing process, but also in the gravelly material or drift 

 that covers the country, and over the slopes of .the valley. 

 At places along the valley where the descending waters meet 

 an obstacle or a projecting rock, both in the river bed and 

 on the declivities, " pockets " of gold are found. Certain 

 layers of the drift are especially rich in the metal. This 

 drift material is explored by turning the streams across it by 

 artificial channels, where nature has not prepared the way, 

 and thus the gold is separated and gathered. 



The gold is mostly in thin scales or grains, usually of quite 

 small size, and sometimes in plates or lumps ; occasionally 

 in masses of fifteen or twenty pounds, mixed more or less^ 

 with quartz./ Each region is generally 

 distinguished by some peculiarity in the 

 form or size of the scales, or their color, 

 the lighter colored containing the most 

 silver. Some of the plates are beauti- 

 fully crystallized in dentritic or plumose 

 forms made of united crystals. A few 

 simple crystals of large size have been 

 found. The annexed figure represents 

 one of natural size, figured and described 

 by Mr. Alger, of Boston. 



The gold of the alluvial washings, as in other cases, has"" 

 been derived from gold-bearing rocks. ' By some long action 

 of denudation, those rocks have been extensively worn down 

 to gravel and sand, and the gold is distributed abng the 

 water courses or on the slopes. As the metal is s© very 

 heavy — seven times heavier than the gravel — it has mostly 

 been dropped by the waters high up the streams. The 

 smaller scales have been carried farthest away, and no doubt 

 minute traces exist throughout the Sacramento valley. The 

 forms of the scales have arisen partly from the original la- 

 mellar form in the rocks, and partly from the process of wear.}/ 



Quartz veins, rich in gold, have been found in many parts 

 of the country, and great efforts have been made to work 

 them, especially in Nevada, Tuolumne, and Placer counties. 

 For a knowledge of particular localities in California, see an 

 article by W. P. Blake, in the American Journal of Science, 

 volume ix, page 72, 1855. 



