Annual report of the State Mineralogist for the year ending ... . uartz from six totwelve feet thick. On the west of this quartz, and separating it fromthe gouge, are several feet of Mariposite. On the east are twenty feet oflight green talcose slate, followed by a dark, jointed slate. Both arefilled thickly with minute quartz seams lying in the stratification, andare intersected by others which dip down toward the large vein. Allthis portion carries more or less free gold and sulphurets, and is minedfor some distance. The slates are rendered so siliceous by their proxim-ity to the vein, that
Annual report of the State Mineralogist for the year ending ... . uartz from six totwelve feet thick. On the west of this quartz, and separating it fromthe gouge, are several feet of Mariposite. On the east are twenty feet oflight green talcose slate, followed by a dark, jointed slate. Both arefilled thickly with minute quartz seams lying in the stratification, andare intersected by others which dip down toward the large vein. Allthis portion carries more or less free gold and sulphurets, and is minedfor some distance. The slates are rendered so siliceous by their proxim-ity to the vein, that their identity with those a hundred feet awaycould hardly be thought possible. A dike of chlorite and feldsparappears in the green schists (296). Its dip as well as that of the slatesis vertical. The dip of the vein is about 80 degrees. The quartz of the main vein of the Dorsey Mine, just north of theTrio, is forty feet thick. It is very bunchy and sometimes almost dis- 5 27 54 REPORT OF THE STATE MINERALOGIST. 19- Section through theLode at the Alabama appears; dip 80 degrees. The paying portion is on the hanging wallside, where the gold is often found in graphitic slates. There is gouge onthe hanging wall, and also a narrow one between it and the foot wallportion. A small amount of tetrahedrite and azurite occur in themassive quartz of the foot wall side. A quarter of a mile east of the Trio, a vein of quartz, fifteen feet wide,outcrops by the road. Near Jamestown, on the west side of WoodsCreek, there is a hill which rises about one hundred and seventy feet,and though it shows no large seams of quartz, yet it is impregnated withmineral matter in a manner similar to that of portions of the MotherLode. Small veins of quartz carrying gold are scattered through it, andin surface decomposition it presents an appearance very similar to thatof the vein matter of the lode, excepting that there is no former crystalline structure of this rock is still apparent in
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