Bulletin . mprobablethat future work would develop an important body of ore at this shaft was filled with water at the time of the field work and was, 112 GEOLOGY AND ORE DEPOSITS OF THE VIRGILINA DISTRICT. therefore, not accessible for study, and the statements in regard to it are,therefore, based on an examination of the material on the dump and onreports of men who worked in the place. At the opening, about one-fourthmile south of this shaft, the conditions are somewhat different. So far ascould be determined from the abandoned and caved pit, the vein is welldefined but narrower,
Bulletin . mprobablethat future work would develop an important body of ore at this shaft was filled with water at the time of the field work and was, 112 GEOLOGY AND ORE DEPOSITS OF THE VIRGILINA DISTRICT. therefore, not accessible for study, and the statements in regard to it are,therefore, based on an examination of the material on the dump and onreports of men who worked in the place. At the opening, about one-fourthmile south of this shaft, the conditions are somewhat different. So far ascould be determined from the abandoned and caved pit, the vein is welldefined but narrower, and, judging by material on the dump, contains verylittle calcite. The ore also differs from that at the Blue Wing and Springshafts in that it contains specular hematite in excess of the copper-bearingsulphides. Bomite and chalcocite are present, but in all the materialavailable for examination were found to be subordinate in amount to thehematite. Hematite occurs with the sulphides in all the mines of the. Fig. 8.—Blue Wing vein at the south face of the 100-foot level. On the right isschist carrying streaks of quartz. In the middle are barren quartz and calcitewith a band of ore in the center. On the left is schist containing quartz lensesand ore. (After W. H. Weed.) district, but only in this one prospect is it present in great abundance. Itsrelation to ore and gangue minerals, so far as noted, is the same in allcases, that is, intergrown and contemporaneous with them. Only at the Blue Wing shaft has development work gone far enoughto afford data on the pitch and other characteristics of the ore shoots, andeven in this instance it is not extensive enough to warrant much in the wayof generalization. It can be stated, however, that the ore does occur indefinite ore shoots in which it shows a tendency to be segregated largely indifferent places in the vein, but that this segregation is in no place com-plete, and that smaller but important amounts of ore are distributed irregu
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