Oro City, Colorado
Oro City, now a ghost town, was an early Colorado gold placer mining town located near Leadville in the California Gulch. Oro is the Spanish word for gold. Oro City was the site of one the single richest placer gold strikes in Colorado, with estimated gold production of 120,000 to 150,000 troy ounces (4 to 5 metric tons), worth $2.5 to $3 million at the then-price of $20.67 per troy ounce.
The site of Oro City is at 39°14′05″N 106°15′08″W / 39.23472°N 106.25222°W. It is in California Gulch, about a mile northeast of Leadville in the Mosquito Range of Lake County, Colorado, United States.
Gold was discovered in the area in late 1859, during the Pike's Peak Gold Rush. However the initial discovery, where California Gulch empties into the Arkansas River, was not rich enough to cause excitement. On 26 April 1860, Abe Lee made a rich discovery of placer gold on California Gulch six miles east of the Arkansas River, and Oro City was founded at the new diggings. By July 1860, the town and surrounding area had a population of 10,000. An estimated $2 million in gold was taken out the first summer from California Gulch and nearby Iowa Gulch, but within a few years the richest part of the placers had been exhausted, and the population of Oro City was several hundred. Many claims (each measuring 100 feet along the stream) were consolidated, and worked by ground sluicing. A ditch was dug in 1877 to provide water for hydraulic mining, but the hydraulic mining was reported to be unsuccessful.
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