114 SILVER-LEAD DEPOSITS OF EUREKA, NEVADA. 



section with the quartzite is laid bare in the deeper workings of all the 

 mines except the Richmond and Albion. It is accompanied by an auxiliary 

 fissure between quartzite and limestone which joins it below. 



conditions beiow the junction of the two fissures. — Where the two fissures conie to- 

 gether in all the mines southeast of the compromise line the ore has been 

 found filling the fissure between the quartzite and the limestone, or between 

 the quartzite and the lower belt of shale. Whether this will continue to be 

 the case as the fissure is followed downward is a matter of speculation. It 

 is likely, however, that when the lower wedge of limestone widens out the 

 ore bodies will take on their usual irregular character, although they will 

 be no doubt in some way connected with the fissure to which they owe 

 their origin. 



Conditions northwest of the compromise line. Tliecliailge which takes place ill the 



Richmond ground soon after the compromise line is passed has been fully 

 explained. The two ore chutes, called, respectively, the west ore body 

 and the east ore body, have the complexion of two distinct lodes in lime- 

 stone. Whether the Potts chamber, which forms a part of the east ore 

 body, actually touched the quartzite or not is uncertain, but, at any rate, 

 it was within a few feet of it. This ore body, however, does not approach 

 the quartzite in any other place. The west ore body touches the quartzite 

 in the Eureka ground near the compromise line, but in all other parts of 

 the mine occupies a position about midway between the secondary fissure 

 on the quartzite, and the main Ruby Hill fault to the northeast. As these 

 two fissures are gradually coming together, and, no doubt, meet at greater 

 depth, it is evident that if these two ore chutes continue down they will 

 eventually form the filling between the two fissures. From the present 

 appearance of the ground it would seem as if the ore-channel which fed 

 the east ore body was near the compromise line, and that it was on the 

 main fissure which is exposed in the winzes from the seventh, eighth, and 

 ninth levels of the Richmond near that line ; and that the source of the ore 

 of the west ore body was the system of fissures which branch out from 

 small ore bodies, extending from the sixth to the ninth levels near the A C 

 line. The fact must not be overlooked that there is a connection between 

 these two ore chutes along the quartzite in the Eureka ground; that is to 

 say, there is a fissure with ore in it here and there. It is, however, impos- 



