okee County and of Oregon, is described in a letter to Dr. Charles F. Chandler, of the Columbia College School of Mines.1
Prof. Fredrich Wohler, of Gottingen, mentions having observed in the
native platinum sands of the Trinity River, Oregon, transparent zircons
associated with laurite, sulphide of ruthenium and osmium, iridosmine,
chromic iron, etc., and microscopic rounded crystals which he supposed
were diamonds. In a subsequent communication, dated Gottingen, August
8, 1869, Professor Wohler continues: "On examination under the
microscope the mineral powder which had been freed from platinum, gold,
chromic iron (in part), silica, iron and tin, and from which the
ruthenium, etc., had been removed by aqua regia, besides many grains of
chromic iron and beautiful hyacinth crystals, colorless and transparent
grains resembling quartz were observed; but besides these, grains
resembling rounded diamond crystals were detected." He then describes
in full his methods of testing these grains, and expresses his
conviction that they were true diamonds.
A
few small diamonds have been found in the placer diggings of Idaho, of
about the same quality and occurring under the same conditions as those
in California. In neither region have they been made the object of
special search, those found having been picked up by miners while
washing the gravel for gold. Fragments of diamonds have been noticed in
the tailings from the quartz mills, being the remains of stones broken
under the stamp. About twenty years ago, quite an excitement prevailed
for a time over Idaho diamonds. Local and mining papers, during the
latter part of 1865 and the spring of 1866, had many references to the
reported or anticipated diamond-yield of that territory. Small
crystals, answering to all the usual tests, were said to be abundant in
a tract of country some forty miles square, between Boise City and
Owyhee. After a few months the excitement subsided, and the ordinary
quartz-crushing industry resumed its sway over the attention of the
people and the press.
In the latter part of 1883, an octahedral diamond is said to have been taken from a placer claim called Nelson Hill, near
»Chemical News, Am. Ed., Nov., 1869, and Am. J. Sci., n., Vol. 48, p. 44, Nov., 1869.
