Colorado Revised Statutes Title 34. Mineral Resources § 34-24-108. Scales--weights certified

(1) It is required that every corporation, company, or person engaged in the business of mining and selling by weight, and where workmen are paid on a tonnage basis, to produce and constantly keep on hand, at the proper place, the necessary scales and whatever else may be necessary to correctly weigh the coal or other minerals mined and taken out by the workmen or miners of such corporation, company, or person. It is the duty of the inspector of weights and measures of each county in which the coal or other minerals are mined and sold to visit each mine operated therein once each year, unless oftener requested by the operator or the miners, to test the correctness of the scale. If in any county there is no inspector of weights and measures, then the district inspector of the district in which the mine is located shall be required to test the correctness of such scales within a reasonable time after application is made by either the operator or the miners.

(2) All weights necessary for testing and adjusting scales shall be duly certified and provided by the operator.