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predicted the finding of diamonds here from the similarity of the gravels to those of Brazil in which diamonds are obtained.
Later
finds of diamonds have been made near Ekaterinburg and in Werchne
Uralsk and Troitzk in the Government of Orenburg; likewise in
connection with auriferous sands.
Diamonds
have also been found in Lapland in the vicinity of Var-anger Fjord on
the Arctic Sea. They occur in river sands, together with garnet,
quartz, rutile, and other minerals usually found accompanying diamond.
These diamonds are small and scarce.
British
Guiana has recently come into prominence as a field which may produce a
profitable supply of diamonds. Small stones were first found here about
1890, and work has been continued until now a considerable amount of
mining is carried on. The locality is along the Upper Mazaruni River,
two hundred and fifty miles south of the town of Bartica. The journey
to it is a long and difficult one, all supplies requiring to be
transported over a narrow trail through a tropical jungle. The diamonds
occur in a formation of sandy clay with other pebbles and ironstone
nodules. They are separated by washing the clay in sieves of
one-sixteenth inch mesh to remove the fine particles, and are then
picked out by hand. The yield is quite remunerative, nine men having in
one instance obtained four hundred stones by working eighteen days. The
stones are small in size, few being above two carats weight, but they
are of good quality. Several companies have been organized to work the
deposits, and a measurable output is likely to be obtained.
The
occurrence of diamonds in the United States is largely confined to two
regions; the first a belt of country lying along the eastern base of
the southern Alleghanies from Virginia to Georgia, while the other
extends along the western base of the Sierra Nevada and Cascade ranges
in northern California and southern Oregon. There is also a third, of
less importance, belonging to the Kettle moraine district of southern
Wisconsin. One of the diamonds found in the southern Alleghanies
weighed 23| carats. It was found in 1855 at Manchester, Virginia, and
is usually known as the Dewey diamond from the name of its one-time
owner. Eight or ten diamonds, varying from one to four carats in
weight, have been found in various localities in North Carolina; ten or
twelve counties in Georgia have furnished one or more small stones, and
one or two are reported from South Carolina. These diamonds have all
been found loose in gravels, and have been obtained either while
washing the gravels for gold, or in digging wells, or they have been
picked up by children. A resemblance of certain strata in
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