Minerals—The Building Blocks of Rocks - The Changing Earth: Exploring Geology and Evolution - page 72

4. Hydraulic mining in California in which strong jets of
water washed gold-bearing sand and gravel into sluices. In
this image taken in 1905 at Junction City, California, water
is directed through a monitor onto a hillside. Hydraulic
mining was efficient from the mining point of view, but
caused considerable environmental damage.
5. Reports in 1876 of gold in the Black Hills
of South Dakota resulted in a flood of miners
that led to hostilities with the Sioux Indians,
and the annihilation of Lt. Col. George
Armstrong Custer and 260 of his men at the
Battle of the Little Big Horn in Montana. This
view shows the headworks (upper right) of the
Homestake Mine at Lead, South Dakota, in
1900. The headworks is the cluster of
buildings near the opening to a mine.
Image not available due to copyright restrictions
7. 8. This image
shows the head-
works of the Yellow-
jacket Mine at Gold
Hill, Nevada, and
the inset shows
silver-bearing quartz (white) in volcanic rock. This largest silver discovery in North
America, called the Comstock Lode, was responsible for bringing Nevada into the
Union in 1864 during the Civil War, even though it had too few people to qualify for
statehood. The Comstock Lode was mined for silver and gold from 1859 until 1898.
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