Mining Engineering key terms

The portion of a measured or indicated mineral resource that can be economically and legally extracted at the time of reporting, after applying mining, metallurgical, economic, and regulatory modifying factors.

A concentration of solid material in or on the Earth's crust in such form and quantity that economic extraction is potentially feasible; it is reported with confidence categories but without proven economic viability.

The minimum grade of material that is classified as ore and sent to processing rather than treated as waste, chosen so that extracted material covers its own mining, processing, and reclamation costs.

The concentration of a valuable element or mineral within ore, usually expressed as a percentage, grams per tonne, or parts per million, and used to decide whether material is economic to process.

The unintentional mixing of waste rock or low-grade material into ore during mining, which lowers the grade delivered to the mill and must be estimated when planning stopes and reserves.

The ratio of waste material that must be removed to the ore extracted in an open pit, commonly reported as waste tonnes per ore tonne or as cubic metres per cubic metre.

A horizontal step or ledge cut into the wall of an open pit or quarry, providing a working platform for drilling, blasting, and loading while controlling wall stability and slope angle.

A surface extraction method in which ore and waste are removed from progressively deeper benches, used where the deposit lies close enough to the surface for the overburden to be removed economically.

A surface mining method that removes long parallel strips of overburden to expose a shallow, usually tabular deposit, backfilling earlier strips with waste as mining advances across the land.

The soil and rock lying above a mineral deposit that must be excavated and removed before the ore can be mined, and which is typically placed on dumps or used for rehabilitation.

Rock material that contains no economic mineral value or falls below the cut-off grade, mined and transported to dumps rather than to the processing plant.

A constructed pile of waste rock or overburden removed during mining, designed with controlled slopes and drainage to remain stable and to allow eventual revegetation.

A vertical or steeply inclined excavation from the surface used to reach underground workings, providing access for personnel, materials, ventilation, and hoisting of ore and waste.

An inclined roadway driven from the surface to connect with underground workings, allowing rubber-tyred vehicles such as trucks and loaders to travel between surface and underground levels.

A horizontal or near-horizontal tunnel driven from the surface into a hillside to reach and drain an orebody, often used where topography allows gravity drainage and vehicle access.

A horizontal or near-horizontal underground excavation that follows a vein or orebody, or connects other workings, and is used for access, ventilation, and ore transport.

A horizontal tunnel driven at an angle to the main orebody or drift, typically to intersect and explore a vein or to connect parallel workings for ventilation and haulage.

An inclined underground roadway connecting levels or stopes, used by mobile equipment and typically graded to allow loaded trucks to travel safely between elevations.

A vertical or steeply inclined underground excavation driven upward, used to connect levels for ventilation, ore passes, or access to stopes.

A vertical or steeply inclined excavation driven downward from an existing underground level to connect with a lower level, serving ventilation, access, or ore handling.

The underground excavation from which ore is extracted, whose shape, size, and support method are designed around orebody geometry, rock mass conditions, and required production rate.

An underground mining method that extracts ore in a series of rooms while leaving regular pillars of unmined material to support the overlying roof, suited to flat-lying, competent deposits.

A block of unmined rock left in place to support the roof or hanging wall of an underground opening, sized according to the loads it must carry and the strength of the rock.

Waste rock, tailings, or cemented material placed into mined-out stopes to support surrounding rock, reduce surface subsidence, and allow recovery of adjacent ore pillars.

The engineering practice of assessing rock mass behaviour and designing support, pillars, and excavation sequences so that underground openings remain stable and safe during mining.

A numerical classification of rock mass quality based on intact rock strength, drill core quality, discontinuity spacing and condition, groundwater, and orientation, used to select support and design excavations.

A tensioned steel bar or cable installed in a drilled hole to reinforce rock around an excavation, holding fractured blocks together and anchoring them to more competent rock behind.

Concrete or mortar sprayed pneumatically onto excavated rock surfaces to provide immediate surface support, seal loose material, and prevent small rock fragments from falling.

The proportion of a drilled length of rock recovered as core, expressed as a percentage of the cored interval, used to assess rock quality and drilling conditions.

A rotary drilling technique using a diamond-impregnated bit that cuts a cylindrical core of rock, allowing geologists to log geology and sample intervals for grade determination.

The laboratory analysis of a sample to determine the concentration of a target element or mineral, producing the grade values used in resource estimation and production accounting.

The systematic collection of representative portions of rock, ore, or process streams for analysis, designed to avoid bias and to reflect the true grade and variability of the material.

The controlled use of explosives to break rock, designed through blast hole pattern, charge weight, and initiation timing to achieve fragmentation, displacement, and wall stability targets.

The size distribution of rock broken by a blast, which affects loading productivity, crusher throughput, dilution, and the cost of secondary breakage.

A chemical mixture that detonates rapidly to release gas and energy, selected for rock blasting by properties such as density, velocity of detonation, water resistance, and fume characteristics.

The vertical transport of ore, waste, personnel, and materials through a shaft using a drum or friction winder, rope, and conveyance such as a skip or cage.

A vertical or steeply inclined opening in which broken ore is stored and transferred by gravity from a higher mining level to a lower haulage level or loading point.

A continuous belt or chain system that transports bulk material such as ore or waste over long distances, offering high capacity and low operating cost compared with truck haulage.

The size-reduction processes of crushing and grinding that liberate valuable minerals from gangue, consuming large amounts of energy and setting the feed size for downstream separation.

The first stage of size reduction, breaking run-of-mine ore into smaller pieces using jaw, gyratory, cone, or impact crushers before grinding or further processing.

The fine size-reduction of crushed ore in tumbling mills such as rod, ball, or SAG mills, performed in water to produce a slurry suitable for mineral separation.

The state in which valuable mineral particles are physically separated from gangue during size reduction, allowing a subsequent separation process to recover them efficiently.

A separation process in which valuable mineral particles are made hydrophobic and attach to air bubbles rising through a pulp, forming a froth that is collected and dewatered.

The product of a mineral separation process that is enriched in valuable minerals and sent to smelting or refining, with the remainder reporting as tailings.

The fine waste material remaining after valuable minerals have been extracted from ore, stored in engineered impoundments or backfilled into underground workings.

The percentage of a valuable element or mineral in the feed that reports to the concentrate or product, used to measure process performance and to calculate payable metal.

The comparison of predicted ore tonnes and grades from the resource model with actual mined and processed results, used to identify and correct estimation and operational errors.