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ECONOMIC GEOLOGY OF SILVERTON QUADRANGLE, [bull. 182. 
to one large stope extending nearly to the surface where the original 
Vanderbilt shaft was sunk. The ore body that once filled this stope 
was evidently of lenticular form, the maximum dimension nearly ver- 
tical, and the mean diameter nearly north and south. Around the 
periphery of the lens the ore body wedged out completely. I was unable 
in the accessible portions of the stope to recognize any dominant fis- 
sure of which the lens of ore might be considered as filling an enlarged 
portion. Nevertheless it was by following the so-called slips or gouges 
Fig. 17.— Plan of a portion of the underground workings of the Genesee- Vanderbilt mine. 
in the country rock that the ore bodies were always discovered when 
not found by drilling (fig. 18). 
Mr. T. E. Schwarz has pointed out that the principal "ore break" 
of the G-enesee-Vanderbilt turned through an angle of about l-tO° in 
passing from the surface down to the 600 level. This is indicated in 
fig. 10, taken from Mr. Schwarz's paper. 1 
According to Mr. Otto J. Schulz, of St. Louis, at present trustee of 
the Genesee- Vanderbilt mine, there were four separate pay shoots on 
the surface, only one of which was explored to the 700 level. The best 
ore occurred at a depth of about 250 feet below the collar of the main 
shaft, and extended down to within about 20 feet of the 300 level. 
1 Trans. Am. Inst. Min. Eng., Vol. 26, 1896, p. 1058. 
