runofmine

Run-of-mine (ROM), often written as runofmine or abbreviated ROM in mining literature, refers to the material removed from a mine or quarry that is delivered to the processing plant before any beneficiation or processing steps. ROM typically includes a mixture of ore and adjacent waste rock as it is mined, and it represents the raw feed for crushing, grinding, and beneficiation.

ROM is characterized by its variable composition, grade, and physical properties, which can change with mining geometry and geology. Because the material is often heterogenous, operators use sampling and reconciliation to estimate the average grade and tonnage of the ROM feed. The ROM is usually hauled to a processing area and may be placed on stockpiles to balance milling capacity and ensure a steady feed to the plant.

Stockpiling and handling are common aspects of ROM management. ROM stockpiles help absorb production fluctuations, facilitate blending, and manage moisture content, dilution, and segregation that can affect downstream recoveries. Proper ROM management supports accurate ore grade control, plant performance forecasting, and reconciliation between mined material and processed product.

In project economics and reporting, ROM tonnage and average grade feed into mine plans, processing recoveries, and revenue forecasts. The term emphasizes the material as it exists in situ or at the gate, prior to beneficiation, and serves as a practical basis for planning and performance assessment in mining operations. See also ore, ore grade, stockpile, and mineral processing.