Geology Reference
In-Depth Information
Riddle in Douglas County, where the principal deposit
is lateritic nickel in the form of the pale green mineral
garnierite. Mining claims were first recorded in 1939,
and extraction operations involve cutting parallel level
benches around and down the mountain side 50 feet
apart. Diesel shovels dig and load the ore, but in recent
years only about half of the ore recovered is rated as
acceptable for further processing. Claims were held by
the Hanna Mining Company which operated here from
1954 until closure in 1987. Two years later the smelter
was reactivated as the Glenbrook Nickel Company.
Other significant nickel deposits in the Klamath
Mountains are on Woodcock Mountain in the Illinois
River valley and at Eight Dollar Mountain near Cave
Junction, both in Josephine County.
valley, Pearsoll Peak, Chrome Ridge, Takilma, and
Vulcan Peak. Of these, the largest chromite producer
was the Oregon Chrome Mine located in Josephine
County about 20 miles west of Grants Pass in the
central Illinois River area. Here individual layers of
lode chromite 20 feet thick, occuring in a massive body
of ore, produce up to 5,000 tons. In Josephine County
a total of 48,941 tons of chromite ore was mined from
1917 to 1958. Only in times of national emergencies,
during World War I, World War II, and between 1952
and 1958 when the U.S. government was stockpiling
strategic materials, was Oregon chromite of economic
interest.
Chromite
Like nickel, chrome ore as chromite is found
throughout the Klamaths deep in ophiolite rock
sequences. Mines were begun in the Illinois River
Chrome ore-buying depot, Grants Pass, 1953.
(photo courtesy Glunz Photo Studio)
