1816 REPORT OF THE CHIEF OF ENGINEERS. 



In giving the ton- value of the ore it is frequently placed in ounces. This is, cor- 

 rectly speaking, the proper mode, though not always the popular one. At the time of 

 the examination of the mines the value of the standard silver ounce was $1.20. An 

 increment of one-fifth to the ounce per ton will therefore represent the money value 

 when otherwise denominated. 



THE SUMMIT DISTRICT 



is some 27 miles southwest of Del Norte, reached from the latter point by a fine toll- 

 road, and lies mainly upon the slopes of South Mountain, a divide between the water 

 of the North and South Forks of the Alamosa. 



This is a most remarkable gold district. It may be said to consist chiefly of a single 

 mine ; for, while the mountain is covered with stakes, there being in all 2,300 locations 

 upon it, one of them is of immense value, some half a dozen are worth having, and 

 the whole of the rest are not worth $5 at present. 



No well-defined veins or lodes have as yet been found, as, in true fissure formation, 

 the mineral-bearing rock, consisting of "rotten" or decomposed quartz, carrying free 

 gold, the metal being free from impurities and more easily milled than any other gold 

 ore in Colorado. 



The principal mine of the district is the Little Annie, other prominent lodes being 

 the Golden Queen, Major, Yellow Jacket, Ida, Golden Star, Summit, and Odin. 



The Little Annie having proven very valuable, it was surrounded upon every side 

 with locations, but up to the present time none of these have given positive indica- 

 tions of deposits of the same character and value. 



Assays of Little Annie ore have varied from a small amount to many thousands of 

 dollars. The average mill-runs have been $102 per ton, the best ore being $150, tail- 

 ings $48, the cost of mining and milling being $12, leaving a large profit to the stock- 

 holders or footholders of the mine. The lode was 85 feet below the surface, the pay- 

 streak, so called, being from 20 to 25 feet wide. This is remarkable as being the 

 highest mine in the world, lying at the edge of timber-line and not far below 12,000 

 feet, the reduction-works in the gulch at the base of the hill being about 11,200 feet 

 above the sea. This was one of the best paying and most economically managed 

 properties found in the San Juan, and can scarcely be surpassed in the whole of Col- 

 orado. At the time of the first visit (June 30, 1877) there had been taken to date from 

 the opening of the mill, as Ave were informed by Mr. C. E. Bobbins, the treasurer and 

 chemist of the company, $105,000, of which $47,000 had been paid out in dividends, 

 the balance being expended in the plant, including a 10-stamp mill, and items of cur- 

 rent expenses. A tramway of over 2,000 feet in length conveys the ore from the dump- 

 pile at the mine to the works below. 



In June the following stamp-mills were in operation at the Summit, reducing ore of 

 the Little Annie : 



Name of mill. 



Number of 

 stamps. 



Daily ca- 

 pacity. 



Little Annie 



10 

 10 

 10 

 5 

 30 



Tons. 



8 



Golden Queen 



8 



Golden Star 



12 



The Adams-Miller 



4 



San Juan 



22 







The latter was temporarily suspended, undergoing repairs. In addition thereto was 

 the Bo wen Mill, of 24 stamps, idle. 



PLACERS. 



Presuming, from the existence of the valuable auriferous deposits upon the slopes of 

 South Mountain trending to the north, that valuable bars would be found in the 

 gulch below, the owners of the Little Annie made extensive preparations for placer 

 mining therein. Their anticipations have been more than realized. 



A magnificent nugget was shown us, obtained in a " cleaning up " early in August, 

 the rock and mineral weighing 5J pounds. The weight of the gold was estimated at 

 20 ounces; the value of the gold ounce with premium then existing being $20.67, there 

 would result a "find" of over $400. 



Numerous and varied have been the theories as to the geological character of the 

 deposits upon the mountain, but that it partakes of a pocket or limited nature is ap- 

 parently demonstrated in its surface existence, at least by the results of the bars be- 

 low. In the various cleanings during the placer operations, nothing was realized, 

 from any part of the stream, except from the portion immediately below the mine. 



