Oretonnagebased

Oretonnagebased is a framework used in mining economics to base project evaluation and planning primarily on ore tonnage. In this approach, the total mass of ore available or to be mined is treated as the central driver of feasibility, rather than focusing exclusively on ore grade or metal content.

Methodology: Starting from geological estimates of total ore tonnage, the analysis links potential production, capital and operating costs, and revenue to grade, metallurgical recovery, and metal price as conditioning factors. Cut-off grades determine payable ore, and tonnage-based reserves and resources may be reported alongside traditional grade-based figures.

Applications: It is used in early-stage scoping studies, prefeasibility analyses, and some contract frameworks where volumetric measures support communication with investors or lenders. The approach can supplement grade- and recovery-based assessments to provide a project-scale perspective.

Advantages and limitations: The approach offers simplicity and a direct link to production planning and budgeting. Limitations include the risk of undervaluing high-grade, low-tonnage zones or overemphasizing tonnage when grade or recovery is uncertain. Results should be interpreted with grade, recovery, and price assumptions in mind.

See also and example: Related concepts include ore grade, cut-off grade, and grade–tonnage curves. For example, a deposit with 50 million tonnes of ore at an average grade of 2 grams per tonne and 85 percent recovery presents a different risk profile than a smaller higher-grade body, illustrating the need to consider all factors in a tonnage-based assessment.