THE COMSTOCK LODE. 43 



The two quartz veins do not extend southward beyond the middle of the 

 Belcher ground. Whether they were originally one vein, of which the west 

 body is a faulted top, or whether they were distinct fissures, is, perhaps, an 

 open question ; but be that as it may, south of the Belcher shaft the conditions 

 are greatly changed. There is but one vein of quartz. It dips west from 

 the surface at a sharp angle, usually 50°, and in depth bends to the vertical, 

 and finally inclines to the east. This sheet of quartz extends from the 

 Uncle Sam to the Belcher, swelling and pinching quite irregularly, and con- 

 taining, through a zone from 200 to 400 feet below the surface, scattered 

 bunches of ore. In the Overman this silver-bearing area is 500 feet from 

 north to south, the most valuable development being from the 206-foot to the 

 406-foot levels, where nine small stopes have been made in a vein varying from 

 six to ten feet wide. 



The position and limited extent of these argentiferous spots is shown 

 on the longitudinal elevation ; Atlas-Plate 6. The whole mass of quartz 

 between and around them is also charged with silver minerals, but not richly 

 enough to pay for working. It would be quite proper to consider them all as 

 parts of one low-grade ore-body, whose true limits cannot be definitely assigned, 

 since the only clues to the bonanza-outlines are the measurements of actually 

 stoped ground. 



In the region of the Belcher bonanza there is nothing which at all cor- 

 responds with the east quartz body of the Crown Point. The following is 

 the arrangement in the middle Belcher ground. The east selvage rests directly 

 on country propylite, with an inclination west of 45°; it averages three feet 

 thick of tough, dark gray clay, and contains numbers of small, rolled quartz 

 and limestone pebbles, from the size of a pea up to that of a hen's egg; those 

 of quartz remaining firm, the limestone being always more or less decomposed 

 and powdery. Lying upon this, to the west, is a zone 20 feet in thickness, of 

 mixed fragments of quartz and propylite, reddened with iron oxide from the 

 decomposition of small particles of pyrites, which are in all the vein materials. 

 A thin seam of clay and sand, nowhere more than two inches thick, separates 

 this from a second zone of quartz 30 feet thick, which is quite free from any 

 mixture of propylite fragments, but is itself shattered into irregular blocks, 

 the interstices being filled with fine quartz and infiltrated clays. Three inches 



