orebody

An orebody is a physically continuous body of ore minerals within host rock that can be mined economically with current technology. It is defined by a sufficient grade and concentration of valuable minerals and by a volume large enough to justify extraction, with boundaries inferred from geology, metallurgy, and economic feasibility.

Orebody geometry varies. Common forms include veins or lodes (narrow, elongated bodies along fractures), disseminated deposits (minerals dispersed through rock), and massive sulfide or replacement deposits. The orebody model integrates geometry, grade distribution, and continuity to predict ore in three dimensions.

Formation processes include hydrothermal activity concentrating metals in veins, magmatic differentiation creating disseminations, and sedimentary or metasomatic events producing replacement deposits. Boundary delineation depends on access, processing, and economics, and is refined through drilling and sampling.

Exploration and evaluation use mapping, drilling, geophysics, and sampling to estimate resources and reserves. Metrics include grade (metal per unit mass), tonnage, and metallurgical recoveries. A cut-off grade, determined by processing costs and metal prices, defines the minimum ore viable for mining.

Mining planning relies on orebody geometry to select methods (open pit or underground) and sequencing. Beneficiation and metallurgical treatment aim to recover the metal, with grade control and dilution affecting profitability. Standard reporting distinguishes inferred resources, indicated resources, and proven or probable reserves, reflecting the level of confidence in the orebody model.