Colo. Rev. Stat. § 34-46-104
It is unlawful to transport any used mining equipment except by railroad transportation without first obtaining written evidence of ownership or right of possession thereof by the person transporting the same, or satisfying the local sheriff or other peace officers of the county in which machinery is located that the person desiring to move such used machinery or equipment as defined in section 34-46-101 is responsible and has a legal right to move such used machinery or equipment. Such evidence shall, upon demand of any peace officer or Colorado state trooper, be exhibited, and unless so exhibited, any such officer shall take possession of such mining equipment at the expense, if any, of the shipper and shall hold the same until the provisions of this article have been complied with.
C.R.S. § 34-46-104