LEADVILLE, a city of Colorado, U.S.A., 170 m. S.W. of Denver, at an elevation of 10,200 ft.; the county seat of Lake county, and one of the celebrated mining camps of the world. It is on Federal highway 40S, and is served by the Colorado and Southern and the Denver and Rio Grande Western railways. The population in 1930 was 3,771. It lies amid towering moun tains on a terrace nearly 2 m. above sea-level, at the head of the valley of the Arkansas river. Great concentration and reduction works and smelters mark its location with a cloud of smoke by day and flames by night. In 1926 the mines of Lake county (nearly all in the Leadville district) produced zinc, lead, silver, gold and copper (named in the order of their importance) valued at $3,884,928.
Leadville's extraordinary history began with the discovery of placer gold in California gulch late in 1859. The lucky prospec tors returned the next spring, and established a camp which they called Oro City. By the end of the year it had a population of 5,000, and in 1861 it was the largest town in Colorado territory. in a few years the placer deposits were exhausted, after yielding some $5,000,000, and Oro City dwindled to a small village. The second spectacular period set in after 18;4, when silver-lead ores were recognized by A. B. Wood, an experienced miner and metal lurgist, in boulders that the gold-miners had regarded merely with annoyance as obstructions to their sluices. Active prospecting began.in the spring of 1877. In Jan. 1878, the town was organized and re-named. In 188o the Denver and Rio Grande railway
reached the gulch, and it is estimated there were 35,000 persons in the district. The city now had a population of 15,00o, 28 m. of streets, 5 m. of water mains, 3 public hospitals, an opera-house and an ample supply of saloons; part of it was lighted by gas; the assessed valuation was $30,000,000. It had become the great est silver camp in the world, with over 3o producing mines, ten large smelters, and an output (gold, silver and lead) valued at $15,000,000 in 1880. Silver mining was the chief interest until the slump in the price of silver in 1893. About 1900, zinc began to assume importance, and by 1915 it constituted 65% of the total output of the mines (in value). During the World War the dumps on Carbonate hill were worked over for zinc ore which had formerly been discarded, and in recent years a considerable amount of silver has been recovered from the slag dumps of old smelters. The veins are still far from exhausted; "unwatering" operations give renewed access to old workings; and new ore bodies are still discovered from time to time.
In the early days Leadville was one of the most turbulent and picturesque of the mining camps of the West. There were serious strikes in 1879 and from June 19, 1896, to March 9, 1897. In the course of the latter, many mines were flooded, and the militia was on guard for months; the miners were finally starved out.