For more than a hundred years Colorado’s minerals—products of her long and diverse geologic history—have influenced her development in many ways. The state’s early wealth, stemming from bonanzas in gold and silver, is evidenced by palatial homes, hotels, and public buildings constructed during the first few decades of mining activity. Some of these are still standing—the opera houses at Central City and Aspen, Central City’s famous Teller House, and the Grand Imperial Hotel at Silverton are examples. Many of the stories and legends of Colorado’s gold camps are recounted in _Stampede to Timberline_, by Muriel Sibell Wolle, delightfully illustrated with sketches of old mining towns as they appear today. _Mining in Colorado_, published by the U. S. Geological Survey, also makes fascinating reading, as it contains many historical anecdotes and eyewitness accounts of gold-rush days. Development of the metal-mining areas in Colorado followed a definite sequence. Placer gold was usually discovered first. Recovery of placer gold was followed by mining of gold from veins or “lodes.” Although at first only native gold was mined, gold-bearing compounds such as telluride were soon recognized as an additional source, especially at Gold Hill, Cripple Creek, and of course the camp that came to be known as Telluride. As gold sources were depleted, silver, first produced as a byproduct, became of prime interest. Lead and zinc were in turn byproducts of silver mining. Other metals, notably copper, vanadium, tungsten, and iron, were produced later. Molybdenum is the Johnny-come-lately of the state’s mining industry, but is now the chief metal produced. A uranium boom in the 1950s brought a short rush to western Colorado and new vigor to the economy. Oil was discovered near Canon City in 1862. The nearby Florence field and a small, shallow field near Boulder preceded much greater discoveries in the Denver Basin, the Uinta Basin, and southwest Colorado. Oil reservoirs, confined to areas of sedimentary rock, are found primarily in the Prairie and Plateau Provinces of the state, and recovery of the oil has done much to distribute population to these areas. Coal is also restricted to sedimentary rock areas. Coal production in Colorado has waxed and waned with the years, but has provided fuel for export, for the railroads, for the manufacture of electric power, and for many of the state’s industries. A good picture of present mineral production in Colorado can be obtained from the following summary for 1971, prepared by the Colorado Bureau of Mines: Product Value