ECONOMICAL CONSIDERATIONS. 



367 





this mineral were noticed by Mr. Wadsworth in the washings from Morris 

 Ravine, If present at all, it must be of quite rare occurrence. Zircon, on the 

 other hand, has been frequently met with ; the crystals are always minute. 

 On the whole, the paucity of gems or other minerals in the gold washings of 

 California is rather remarkable, as compared with their abundance in other 

 parts of the world. Specimens of stream tin have been occasionally shown 

 us, but under circumstances which threw much doubt on their authenticity. 



The occurrence of cinnabar with native gold, which has been repeatedly 

 noticed in the Coast Ranges, is also not unknown in the Sierra. A specimen 

 of washings, described as having come from near Placerville, consisted of 

 rounded grains of pure cinnabar, with crystals of magnetite, globules and 

 grains of lead, and scales of gold. This need not excite surprise, as the 

 writer has seen in the auriferous slates quartz veins containing well-defined 

 crystalline masses of cinnabar, which were small in size, but extremely pure. 





Section IX. — Economical Considerations relating to the Working of the Gravels. 



Although this volume does not profess to concern itself especially with the 

 economical aspect of the hydraulic mining business, yet a large amount of 

 information in this department has been gathered in the course of the inves- 

 tigation, as will be seen by reference to the preceding chapters and the 

 Appendices A and B. It is proper, therefore, to pass in review the principal 

 facts, and to devote a few pages to setting forth such of the conclusions which 

 can be drawn from them as may seem of special importance. 



The first question would naturally be, What is the total yield of gold from 

 the hydraulic mining operations? An answer to this question is desirable, 

 as enabling the reader to form a correct idea of the magnitude of the busi- 

 ness, the scientific side of which has been that most prominently presented 

 in the course of this work. As is well-known, all statistics of the yield of 

 the metals in this country are of the nature of guesses, more or less to be 

 depended on in proportion as the parties guessing have had favorable oppor- 

 tunities for forming an opinion, and have been qualified by natural ability 

 and education to make a good use of such opportunities. * 



The yield of gold in the most productive years of gold mining in Cali- 



fornia, 1851 



$ 



* It is hardly necessary to add that disinterestedness is also a sine qua non in forming a valuable opinion in 

 relation to the value and yield of mining property. 





