Gold mining in Colorado, a state of the United States, has been an industry since 1858.
It also played a key role in the establishment of the state of Colorado.
Explorer Zebulon Pike heard a report of gold in South Park, present-day Park County, Colorado in 1807.
Gold discoveries in Colorado began around Denver, traced the placer gold to its source in the mountains west of Denver, then followed the Colorado Mineral Belt in a southwest direction across the state to its terminus in the San Juan Mountains.
The Cripple Creek district, far from the mineral belt, was one of the last gold districts to be discovered, and is still in production.
On June 22, 1850, a wagon train bound for California crossed the South Platte River just north of the confluence with Clear Creek and followed Clear Creek west for six miles (9.7 km).
Lewis Ralston dipped his gold pan in a stream flowing into Clear Creek, and found about a quarter of a troy ounce (worth almost $5, equivalent to $150 today) in his first pan.
John Lowery Brown, who kept a diary of the party's journey from Georgia to California, wrote on that day: "Lay bye.
Gold found." In a notation above the entry, he wrote, "We called this Ralston's Creek because a man of that name found gold here." Ralston continued on to California, but returned to 'Ralston's Creek' with the Green Russell party eight years later.
Members of this party founded Auraria (later absorbed into Denver City) in 1858 and touched off the gold rush to the Rockies.
The confluence of Clear Creek and Ralston Creek, the site of Colorado's first gold discovery is now in Arvada, Colorado.
A gold discovery in 1858 in the vicinity of present-day Denver sparked the Pike's Peak Gold Rush.