lxVlii REPORT OF THE STATE GEOLOGIST. 



Shafter or Bullis mine, and is owned and operated by the Presidio 

 Mining Company, who are now working two mines — the Presidio and 

 Cibolo. In the former, which was discovered in 1880, the mine consists 

 of pockets and bunches of ore of irregular shapes and sizes, generally 

 isolated from each other, imbedded in a limestone country rock, thus 

 forming chamber deposits. 



The Cibolo has the same general character, but, in addition, has an 

 ore body situated in a well defined fissure, and is a contact deposit. This 

 company work their own mill and ship their product as bullion. The 

 mill, which is of ten stamps of the common California pattern, is located 

 on a hillside, so that the ore from the crusher falls to the automatic 

 feeder at the stamps, from which the pulp is lifted to the amalgamates. 

 The amalgam is freed from the excess of quicksilver by straining, as 

 usual, when retorted and fused. This mill averages from thirty to thirty- 

 five tons of ore per day, which yields from forty to forty-five ounces of 

 silver per ton. The motive power is an eighty-horse power engine. 

 There is an ample water supply in Cibolo Creek to permit an increase 

 in the size of this mill and the erection of others as well, and there is 

 also good opportunity to build storage reservoirs along it. There are 

 other locations being worked up, many of which promise good returns, 

 and there is no doubt that this district must soon become one of the 

 centres of the mining industry in Texas. 



IMPORTANCE OF THESE INDUSTRIES. 



From the foregoing description of the occurrence of copper, lead, zinc, 

 silver, and gold, it is clearly evident that we have in Texas deposits of 

 the ores of these metals which are abundant in quantity and of suffi- 

 ciently high grade to fully warrant the claim so often made of our great 

 resources in this direction. The work of the Survey has established 

 the connection and relations existing between many of these ore deposits 

 and the rock materials enclosing them. It has proved the continuity of 

 the veins over considerable distances. It has proved and asserted the 

 value of the ores, and stated the certainty of profitable returns from sys- 

 tematic and intelligent prospecting and mining. It has pointed out 

 places at which prospecting could be carried on, and in some special in- 

 stances has given advice to those at work. The ores are here. They 

 are abundant enough and sufficiently rich to justify the rapid and ex- 

 tensive development of our mining industry, but this development is 

 hindered, not only by l»k of transportation facilities and proper reduc- 



