An ore lens is a lenticular, or lens-shaped, body of mineralization that is thickest in its center and tapers toward its edges, a geometry commonly produced by structurally controlled mineralizing processes rather than uniform sheet-like deposition. Ore lenses are particularly characteristic of orogenic gold deposits and volcanogenic massive sulfide systems, where hydrothermal fluids preferentially deposited minerals within structural traps such as fold hinges, fault dilations, or shear zone openings, producing discrete pods of high-grade material along an otherwise lower-grade structural trend. Because ore lenses can be discontinuous and vary significantly in size, orientation, and grade along their length, they pose particular challenges for resource estimation and mine planning, often requiring closely spaced drilling to define their true extent and reduce the risk of mining dilution at their margins. While the term is most frequently applied in gold mining contexts, similar lenticular geometries can occur in iron ore deposits affected by structural folding and remobilization, where originally tabular banded iron formation units become deformed into thickened, lens-shaped zones of higher-grade enrichment within fold structures.
