Bulletin . rtz. There is no oreexposed except on the north wall, where there is a slight green stain. On the second level south no timbering exists, so that it was notcarloads [of ore] have l>een shipped from this mine, which varied fromshows hard, finely laminated micaceous schists, the schistosity of whichmakes an angle of about 30 degrees with the vein. At the north end ofthis level the vein shows a slaty hanging-wall, with quartz feeders runningoff into it. These feeders wedge off in a few feet, and usually carry quartz ore-body does not show any marked breccia; but in this, as
Bulletin . rtz. There is no oreexposed except on the north wall, where there is a slight green stain. On the second level south no timbering exists, so that it was notcarloads [of ore] have l>een shipped from this mine, which varied fromshows hard, finely laminated micaceous schists, the schistosity of whichmakes an angle of about 30 degrees with the vein. At the north end ofthis level the vein shows a slaty hanging-wall, with quartz feeders runningoff into it. These feeders wedge off in a few feet, and usually carry quartz ore-body does not show any marked breccia; but in this, as inall the mines of the district, there are the usual thin, plated masses ofdecomposed schist. In general, the richer ore is found near the definite association was observed between the occurrence of ore and thecharacter of the various schists cut by the vein. On the first level, 75 feet below the surface, south of the shaft, thevein is 133* feet wide, but converges rapidly in both Fig. 11.—Ideal horizontal cross-section of the Hollowav vein, showing quartz spursfollowing the foliation of the country schist. (After Weed.) Mineralogy.—The gangue minerals, exclusive of fragments and bands ofcountry rock included in the vein, named in the order of their abundance,are: Quartz, epidote, chlorite, hematite, and a little pink feldspar, probablyorthoclase. The ore minerals in the order of their abmidance are: Chal-cocite, bornite, malachite, azurite, and argentite ( ?). cuprite, native copper,and native silver. All the minerals of the vein, except the oxidizationproducts and a part of the chalcocite in the upper portion of the vein, whichis clearly secondary, are intimately and complexly intergrown and arebelieved to be of contemporaneous development. Epidote occurs in thismine in greater abundance as a gangue mineral than in any other mine orprospect in the district, and ealcite is prol)al:)ly a little less abundant than This should read 33 feet. See Wee
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