Bulletin - United States Geological Survey Volume 546 (Paperback)

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1914 Excerpt: ...and these not in detail, but enough has been seen to indicate that they are essentially contact deposits and that there are two distinct modes of occurrence. In the one class the ore bodies, chiefly pyrite with subordinate chalcopyrite and bornite, occur in quartz porphyry near its contact with slates. In the other class the ore bodies, chiefly chalcopyrite and pyrrhotite, prevail in greenstone or serpentine near their contact. Of the occurrence in quartz porphyry the deposit at Almeda is the best known and almost the only example in the district; of the occurrence in greenstone or serpentine near their contact the mine at Takilma, generally known as the Queen of Bronze, has been most fully developed and described,1 but the deposit on Fall Creek is quite as characteristic. ALMEDA MINE (30). GENERAL FEATURES. The Almeda mine is owned and operated by the Almeda Consolidated Mines Co. It is located on the right bank of Rogue River, about 26 miles below Grants Pass, and is reached by stage line and i This mine is described by G. F. Kay in TJ. S. Geol. Survey Bull. 380, pp. 76-78,1909. wagon road 17 miles from Merlin, on the main line of the Southern Pacific. A shorter road (15 miles), avoiding the river but crossing the divide to the raihoad at Leland, was partly completed in 1911. The situation of the mine is advantageous, as it lies in the rugged but passable canyon of a rushing river, cutting directly across the formations, so that the canyon walls afford convenient facilities for economical mining. My examination of the mine was made rather inopportunely on July 10 and 11, 1911, just as the management changed. At that mSJevel U Figure 8.-Plan and longitudinal section of Almeda mine. By P. H. Holdsworth, November 28,1911. time no plans or sections of the min...