CHRYSOLITE MINE. 461 



To the northeast of the Roberts shaft pay ore is cut off by a body of 

 black iron, into which it passes so abruptly that the latter often forms a 

 wall 20 feet in height. Above the black iron is a body of blue lime-sand 

 about one hundred feet in extent. Beyond the ore stopes in the vicinity of 

 the shaft, exploring drifts on the lower (284-foot) level connect to the north- 

 ward with Carboniferous No. 5 shaft, and from there to the westward with 

 Chrysolite No. 5 shaft by an up-raise to the 316-foot level, all in barren 

 vein material. From Carboniferous No. 5, the bottom of which is in disin- 

 tegrated Parting Quartzite similar to that cut in the Roberts shaft, a drift 

 runs due north through White (block) Porphyry and at 200 feet from the 

 shaft cuts White Limestone, which is slightly iron-stained at the upper sur- 

 face. Still farther north, beyond the limits of the Chrysolite claims, the 

 Silver Wing shaft was sunk through White Porphyry into a body of iron 

 vein material, which is evidently a replacement of the upper portion of the 

 White Limestone. Explorations were conducted here under great difficul- 

 ties, owing to the immense in-rush of water, and, so far as they went, did 

 not disclose enough pay ore to justify the owners in pursuing them further. 



The evidence of these northern workings is very conclusive as to the 

 basining-up of the formation to the northwest, and this evidence is further 

 confirmed by the several shafts to the east of the Silver Wing, the Buck- 

 eye, Hazzard, Hercules, Comique, and 0. K., all of which have found a 

 considerable body of iron vein material, either at the rock surface or under 

 a thin covering of White Porphyry, which represents the outcrop in this 

 direction of the Blue Limestone horizon. As in the Silver Wing, the great 

 in-rush of water has proved a bar to extended explorations from these shafts. 



The Gray Porphyry dike separates the two main ore shoots of the 

 Chrysolite ground. Little can be determined about the form of this body 

 in depth, as explorations have not proved it below the Blue Limestone hori- 

 zon. It may be simply a transverse sheet, cutting diagonally across the 

 formations and assuming a vertical position as it approaches the present 

 rock surface. Still, its form, so far as traced, is sufficiently characteristic of 

 the dike type to justify the assumption that it is rather a true dike than a 

 transverse sheet, though the distinction, so far as the deposition of ore is con- 

 cerned, is comparatively unimportant. It is distinctly later than the White 



