ore reserve

An ore reserve refers to the quantity of a mineral that can be profitably mined from a deposit. This classification is dynamic, influenced by fluctuating mineral prices and extraction costs. When mineral prices rise or costs decrease, more of the total mineral inventory can be classified as ore. Conversely, if prices fall or costs increase, previously profitable ore may become uneconomical to extract.1

The determination of ore reserves is a crucial step in mine evaluation and design, particularly for open-pit mining. It involves detailed geological surveys, including drilling probe holes to map the ore body's extent and grade distribution. Economic factors are then applied to create an economic block model, which helps define the final pit outline for extraction. The grade of a mineral deposit, or the concentration of valuable minerals, is a key factor. A mine cutoff grade exists below which mining is not profitable, and this is influenced by extraction costs and expected commodity prices.23