DESCRIPTION OF VARIOUS MINES IN COLORADO. 49 



and partially removed as the shaft is sunk, the hanging wall being Porphyry, and 

 compared to the quartz is very easily worked. Down to water level the mineral 

 was principally carbonates, with occasionally a mass of galena of fifty or sixty 

 pounds. At about ninety feet water was reached, and the mineral was found in 

 the pockets in a crystallized form. It is principally Argentiferous galena, with 

 zinc blende, iron and copper pyrites ; some gray copper and also antimonial 

 silver. The first indication of approach to a deposit of mineral, is the shattered 

 condition of the quartz and an increased flow of water. On top of the pocket, 

 when first opened, is found metallic geodes, weighing from a few ounces to sev- 

 eral pounds. On breaking one open the center will be of pyrites, surrounded 

 with a ring of zinc blende or galena, also spots of gray copper intermingled and 

 a thin band of antimonial silver surrounding the whole between the galena and zinc. 

 Passing below the layer of geodes the mineral is found finely crystallized and 

 easily worked, the bottom of the pocket producing the largest mill returns gen- 

 erally. Usually a thin streak of mineral leads from one pocket to another. At a 

 depth of about 170 feet, a five ton pocket was emptied, and a horizontal streak 

 of mineral was seen on the north side, which, on being followed up led to a 

 larger pocket on about the same level. This would indicate a probability of a 

 very much larger amount of mineral being still in the quartz above than has been 

 taken out. From the latter deposit some very fine geodes were obtained with a 

 center of quartz, both massive and crystallized, and surrounded with the other 

 metals same as those containing a center of pyrites, and out of this a picked 

 specimen of brittle (antimonial) silver gave an assay of 1876^ ounces per ton, 

 although the mill result was not as high by a few ounces per ton as the previous 

 pocket. On breaking through the north wall of this chamber a soft gangue was 

 found, and beyond that the Porphyry, showing that the quartz had been entirely 

 penetrated at this point and giving thickness of about fourteen feet. 



The motive power being mules, a whim and two buckets, it was determined 

 to run levels at a depth of 200 feet, and accordingly that work is being done. 

 Simultaneously, levels in an east and west direction were started. The east one 

 has been run but twenty-five feet and, appearing barren, has been temporarily 

 stopped. At seven feet from the shaft on the west drift a large pocket was cut 

 through and mineral left both above and below ; that above being stoped out by 

 one man, and the level, continued by the rest of the force west, for a distance o f 

 forty-five feet. Here the quartz was found much shattered, and containing con- 

 siderable heavy spar, which is a most excellent indication. But it was found that 

 the quartz here narrowed down to about four feet, and a return level is now being 

 run on the north side of the lode, which will probably develop more mineral on that 

 wall, and when continued so as to open into some of the last pockets emptied in 

 the shaft, will form a most excellent air-conductor and ventilator for new work 

 si ill farther west. 



Among the minerals, I have seen some fine crystals of Franklinite attached 

 to the quartz, and in the decomposed rock near the pockets I have obtained per- 



4— in. 



