COAST RANGE GRAVELS. 



299 



> 



from the work. These have reference to the manner in which the gold is 

 distributed in the detritus with which it is connected. The particles of the 

 precious metal may be quite uniformly scattered through the mass, or they 

 may be almost entirely concentrated within a narrow vertical range : in the 

 latter case the pay-gravel or pay-streak is pretty sure to be on or near the sur- 

 face of the bed-rock; or the lower portions of the detrital mass may be much 

 richer than the strata above; and yet the latter capable of being washed with 

 profit by the hydraulic method, under favorable circumstances, even when the 

 richer portions below have been previously worked out by drifting. Still an- 

 other matter has often to be weighed in connection with gravel mining. The 

 body of gravel may be heavy and rich in gold, but capped with volcanic mate- 

 rials which are of too solid a character to be capable of being washed away — 

 or " cut/' as it is usually called — by the jet from the pipes, even with the use 

 of powder, in which case the hydraulic method cannot be used at all ; or, on 

 the other hand, the capping, whether of volcanic material, which would yield 

 to the force of the water, or of non-auriferous pipe-clay or gravel, may be 

 too heavy to be capable of being handled without incurring more expense 

 than the yield of the auriferous stratum beneath will justify. 



Considering the above-mentioned circumstances influencing the develop- 

 ment of the gravel-mining business, we may expect to find, and do find, a 

 variety of methods employed, corresponding with the various conditions 

 specified. Further on in this chapter some of the economical considerations 

 connected with the hydraulic method, as well as the other kinds of 

 mining employed in the gravel regions, will be briefly set forth. At present, 

 it most concerns us to notice the fact that the gravel deposits of the west 

 slope of the Sierra Nevada almost always contain some gold, and that there are 

 comparatively few localities where they have not been " prospected" to some 

 extent; so that, on the whole, their distribution is pretty well understood. 



The occurrence of bodies of gravel of considerable size in the Coast 

 Ranges has already been alluded to. # Some of these, in the southern part 

 of the State have, in former years, been worked for gold to some extent; but 



4 



it is not known to the writer that any of them are at the present time. By 

 for the larger portion of the Coast Range gravels may without hesitation be 

 set down as nearly or quite destitute of gold, as the activity with which pros- 

 pecting has been carried on during the past thirty years is sufficient assur- 

 ance that but little of value can possibly have escaped the notice of the 



* See aide, p. 22, 23. 



