MINES OUTSIDE THE LEADVILLE DISTRICT. 521 



and just west of the saddle are several prospect holes in a bed of dark-green 

 hornblendic rock, near the upper part of the formation, which is highly im- 

 pregnated with pyrites. In the amphitheater north of the saddle copper 

 pyrites are found in the Archean gneiss, in a gangue of quartz. On the 

 saddle itself a shallow prospect hole called Sammy's Barrel shows a gash 

 vein in the White Limestone a few inches in thickness, which carries galena 

 in a gangue of calc spar. At the eastern end of Hoosier Ridge, at the ex- 

 treme head of Beaver Creek, is the outcrop of a large deposit of iron ore in 

 the upper Carboniferous or Triassic beds, which apparently follows the 

 bedding, and from which specimens of chrome iron are said to have been 

 obtained. 



MOUNT LINCOLN. 



The silver deposits on Mount Lincoln were first discovered in the sum- 

 mer of 1871. In spite of their great altitude, being nearly fourteen thou- 

 sand feet above sea level, they were rapidly opened ; a number of mining 

 towns sprang up at the foot of the mountain ; quartz-mills were built and 

 smelting works erected. For a time they enjoyed great prosperity, but of 

 late years have been in great measure abandoned, and the mining towns of 

 Qiiartzville and Montgomery are now practically deserted. The deposits 

 are principally in limestone. The cause of their abandonment may be 

 found in part in the inherent difficulty of regular development of limestone 

 dep'csits, owing to their frequent want of continuity and to the misconcep- 

 tion on the part of the minei's of the character of the deposits. In great 

 part it is probably also due to the excitement attendant on the discovery of 

 the rich deposits of Leadville, which drew away the fickle miners to new 

 fields. Everything tends to show, however, that the region is one excep- 

 tionally rich in metallic deposits, and that under S3*stematic development 

 its prosperity may be revived at no very distant future. 



The Russia mine (L) is situatcd about five huudrcd feet below the summit of 

 the peak, in a direction south-southeast. The deposits of this mine are found 

 in the Blue Limestone, which here forms the surface of the spur, the over- 

 lying sheet of Lincoln Porphyry having been eroded off. In places, yel- 

 lowish quartzite and a bed of yellow, compact, argillaceous rock, called by 

 the miners porphyry, is still found above the limestone. The ore is prin- 



