Gold Run, near Gold Hill, was the scene of one of the earliest strikes
in Colorado. Gold was found here in December 1858, and was sluiced from
stream sands and mined from veins early in 1859. Active placer mining
lasted only about a year, however, and lode mining dropped off rapidly
as near-surface oxidized ores were worked out. When a smelter was
erected at Black Hawk in 1868, and sulfide ores could be treated, there
was a revival of activity. In 1869 the Caribou and Poorman mines near
Nederland were discovered; they quickly became the most active mines in
the county. The Ward district opened soon after.
In 1872, a gold-silver telluride called petzite was found in veins at
Gold Hill. Renewed prospecting in this area resulted in location of
mines near Sunshine, Salina, and Magnolia. During the years that
followed, new mines appeared almost as fast as old ones were depleted.
In 1892, the peak year, more than $1,000,000 in gold and silver was
produced; total production has been about $25,000,000.
In 1900, a black mineral common in the Nederland area was recognized as
ferberite, an ore of tungsten, and a new rush to the area started.
During the next eighteen years Boulder County was the main tungsten
producer in the United States; about 24,000 tons of tungsten trioxide,
worth $23,000,000, were produced here. The ore was found in nearly
vertical veins six inches to three feet thick, in a lenticular area
about nine miles long extending from Nederland northeast to Arkansas
Mountain, four miles west of Boulder.
Boulder County is characterized by an abundance of small mines. Old
shafts, pits, and mine buildings can be found throughout the central
part of the county. Little mining is done here today; many of the towns
that once peppered these hills have fallen into decay or disappeared
entirely.