Eastern Oregon is to be found along the slopes and among the ridges of the Blue Mountains, where the marine fossils are not covered over by trap-rock. According to Mr. Condon, the older marine rocks, containing fossils of the Rynconella, Cyrtoceras, and other marine shells, may be considered indicative of the vicinage of gold-bearing rock.
The counties of Eastern Oregon, known as gold-producing, are Union, Grant, and Baker. The mineral districts are located on Powder River and Eagle Creek, in Union County; on the head-waters of the John Day, in Grant County; and on Burnt River and the head-waters of Powder River, in Baker County. Quite recently mineral discoveries have been made in the mountains about Goose Lake, in the extreme southern portion of Grant County, but have not yet been sufficiently worked to test their value.
Most of the gold produced in these counties has been taken from placer-mines, which generally have yielded well. Many quartz lodes have also been located, and a few containing free gold have been worked with good results. Quartz-mining has not, however, been carried on to any great extent in Eastern Oregon, the capital required to get out the ore and erect mills being wanting. It remains for wealthy companies in the future to undertake this order of mining.
Silver lodes, some of great richness, have been discovered in Baker County, a number of which are being worked, but not to any great extent. One is said to have yielded at the rate of over $7,000 per ton, by smelting on a common blacksmith's forge. What its working yield has been, we have not yet been able to learn.
Coal, iron, lead, and copper have been discovered in
