Determining the land status is one of the most important parts of prospecting. Counties can provide more specific information on land ownership. Prospecting in Colorado should not be done on private lands without consent of the property owner. Prospecting on federal land is regulated by the BLM and U.S. Forest Service. The BLM and the Colorado Division of Reclamation, Mining and Safety can answer questions about staking claims, mine permitting, and other information about land status.
US Department of the Interior Bureau of Land Management / Mining and Minerals — Mineral prospecting and development information, and specifically how to establish a mining claim; Mining Claims and Sites on Federal Lands; and their Mining Claim Packet.
Colorado Division of Reclamation, Mining, and Safety — comprehensive information on mining programs and regulations for the state.