392 GEOLOGY AND MINING INDDSTRY OF LBADVILLE. 



yet been developed along- the contact. On the extreme north end of the 

 Lime claim, an incline, not indicated on the map, was driven in on the 

 contact until cut off by a wall of Gray Porphyry, standing at an angle of 

 65 with a strike to the east and northeast, This would seem to be an off- 

 shoot from the intrusive sheet in the lower part of the Blue Limestone. 

 The form of this offshoot, shown in Section E, must be understood to be, in 

 the present state of developments, purely a matter of conjecture. That 

 ore bodies have not been found at the contact here is, however, not neces- 

 sarily a proof that they may not exist within the body of the limestone, as 

 will be seen from the description of the next group. Thin beds of shale* 

 carrying Lingula are found at the contact in the Lime and Bull's Eye 

 claims, near the outcrop. 



South Bull's Eye, and Silver Cord Combination. A Considerable body of rich 



carbonate ore was found along the contact and near the outcrop at the 

 south end of the Bull's Eye claim, which has been developed by the 

 so-called South incline. It was extremely irregular in shape, extending in. 

 places fifteen or twenty feet below the contact ; its probable continuation 

 in the Silver Wave ground is apparently even thicker As shown in Section 

 D, this body, like that already described in the Rock mine, occurs just above 

 and on the crest of a fold in the limestone, whose axis has a northeast direc- 

 tion parallel to that of the ore body. The ore was quite rich near the surface,, 

 but became poorer in depth. To the south it passes into black iron (wad), 

 containing little or no silver. The incline, which runs diagonally across 

 the body and follows approximately the contact plane, has at first an incli- 

 nation of 12, and after passing the crest of the fold steepens to an average 

 angle of 25, and for short distances reaches 45 or more ; the contact is- 

 here barren, showing only iron- stained clay and a little Chinese talc. This 

 body, like that of the Rock mine, was one of the earliest developments in 

 the district. 



In laying out the side lines of the Bull's Eye claim it was the inten- 

 tion of the original locators to include within them, as they did so success- 

 fully in the other claims of the Iron Silver Mining Company, the outcrop 

 of the vein or of the upper surface of the Blue Limestone. As it happened, 

 however, the limestone rises at this point over a secondary fold, and the line 



