File:The Mother Lode region of California (1900) (14596965819).jpg

Identifier: motherloderegion00storuoft (find matches)
Title: The Mother Lode region of California
Year: 1900 (1900s)
Authors: Storms, William H., b. 1859
Subjects: Mines and mineral resources
Publisher: Sacramento A.J. Johnston, superintendent state printing
Contributing Library: Gerstein - University of Toronto
Digitizing Sponsor: University of Toronto

View Book Page: Book Viewer
About This Book: Catalog Entry
View All Images: All Images From Book
Click here to view book online to see this illustration in context in a browseable online version of this book.

Text Appearing Before Image:
-hole to avoid flooding of the new workings fromthe old. It eventually became necessary to remove the water throughthe shaft of the old workings. This new shaft has continued to a depthof 1660 feet, having passed through the vein at about the 1200-foot level.There are tanks at the 300-foot level and at the 700-foot level. At thelatter a cross-cut was run west from the station 374 feet, through slateto and beyond the vein, the foot-wall of which was reached 124 feetwest of the shaft. At the 1000-foot level a cross-cut was run 69 feetwest through the vein, which was here 15 feet 6 inches wide, the foot-wall being 58 feet west of the shaft. The foot-wall of the vein was THE MOTHER tODE REGION—CALAVERAS COUNTY. 101 encountered in the shaft 1245 feet from the surface. Cross-cuts in thelower levels run to the westward have encountered two small veinsand two dikes of light-gray intrusive rock. The first vein encounteredis very persistent in strike and dip, though usually small. It has pro-
Text Appearing After Image:
Me-TWOD of- Tin^^ERINC^ in Q>\N\N A^lNErr Fig. 28. duced some rich ore. The ore-shoots of the main vein are of greatlength, varying in width from a few inches to 20 feet. Gouge is alwayspresent on the foot, and sometimes on the hanging-wall. The slateshave a tendency to swell, and are the cause of considerable expense, 102 CALIFORNIA STATE MINING BUREAU. but cannot be compared in this respect to some of the Amador Countymines. The vein is usually banded, and exhibits a branching tendency,there being many spurs running into the hanging-wall, but few into thefoot. The lenses of quartz which are characteristic of this vein fre-quently build up a narrow into a large vein by splicing, and sometimesby overlapping. There is some black slaty material in the vein, butless than is found in many similar mines elsewhere. Large masses ofthe vein quartz are found crushed by pressure and movement, and insome places the quartz disintegrates rapidly from exposure by reason ofthe slaking of the carb

Note About Images