40 BXPLOEESTG EXPEDITION FROM SANTA EE 



( i.-ilistc.) ( {reek*. It generally occurs in fine scales, and but few nuggets of any consid- 

 erable size have been found. The supply of water for washing out the metal is so 



small and irregular that gold-digging here is too uncertain a business to he depended 

 upon as ;i means of subsistence by any considerable number of miners. Only a few 

 Mexican families reside in the vicinity, and these employ but part of their time in gold- 

 washincr. When the quantity of water is sufficient to enable them to wash out the 

 gold, the average gain of each man provided with shovel and shallow wooden wash- 

 pan, lulled, may perhaps be estimated at a dollar per day. 



Some Frenchmen formerly resided here, who, for a long time, carried on mining 

 operations in u somewhat systematic manner. They excavated the gold-bearing rock; 

 Crushed it between blocks of porphyry, made to revolve by mule-power: the gold 

 being extracted by quicksilver. The auriferous rock is said to have yielded about 

 thirty dollars of gold to the ton. With their rude processes of obtaining the -'old it is 

 probable that the operations of these parties were not very remunerative, as they have 

 been now for some years discontinued. An American company has recently purchased ;i 

 proprietorship at the Old Placer; but, as they represent, from the want of proper machin- 

 ery and the difficulty of obtaining laborers skilled in the business, the experiment has so 

 far been unsuccessful. 'The quantity of gold which exists here is, however, evidently 



large, and it is quite possible that, with more ample means, with more skillful operators, 

 and better machinery, these mines might be worked with profit to the proprietors. It is 



possible, too, that something might be done by building reservoirs to increase, Or al 



least to regulate, the supply of water for the placer, and thus render it more produc- 

 tive. It is true, however, that the fall of rain in all this region is both small and exceed- 

 ingly irregular, and the structure of this mountain group, so limited in extent and so 

 simple, would render it difficult, if not impossible, to utilize fully the few and fitful 

 rains by which it is visited. 



The rock containing the gold at the ( )ld Placer has been regarded by some who have 

 visited the locality as an altered sandstone, but there can be, I think, little doubt that it 

 is the gossan of an auriferous quartz vein. The material now excavated is a cellular 

 silicious rock, of which some portions are soft and ochrev, others hard and quart/dike. 

 In some localities it is associated with a sot't vellow tufa, in others with a hard trachyte 

 or porphyry. The same rock recurs in the Cerrillos; and I have received from the 

 gold diggings of I'ike's Peak specimens of auriferous vein-stone presenting precisely 

 the Same characters. 



Co/ijirr. — Considerable copper is found at the Old Placer, though as yet no effort 

 has been made to turn it to account, ami it is doubtful whether the quantity is sufficienl 

 to make it a proper object of attention in an economical point of view. I obtained 

 from there, however, very beautiful Bpecimens of the sulphides of copper and iron, both 



yellow and variegated (chaloopyrite and bornite). 



Iron. — Manv larere masses of magnetic iron ore were noticed about the old Placer, 

 and it is said to occur in abundance there in place. 'This ore is very pure, of a nearly 

 uniform dull black color, less crystalline in appearance, and containing less silica than 

 the Champlain and Canada ores. That which is freshly mined is highly magnetic in 

 character, and often exhibits the properties of the loadstone. 



