Ore extraction is the physical process of removing ore from its natural setting in the ground, encompassing the full range of mining methods used depending on deposit geometry, depth, and grade. Open-pit mining, the dominant method for bauxite, iron ore, and many diamond and gold deposits, involves removing overburden and ore in successive benches using large excavators, shovels, and haul trucks. Underground mining methods such as block caving, sublevel stoping, or room-and-pillar techniques are used where ore bodies are deep or steeply dipping, as is common in many hard-rock gold and kimberlite diamond mines. Alluvial and placer extraction, relevant to both gold and diamond mining, uses dredging, hydraulic sluicing, or excavator-based digging to recover minerals from unconsolidated river, beach, or marine sediments. The choice of extraction method directly affects ore loss and dilution rates, operating costs, and the pace at which reserves are converted into mill feed. Extraction planning must also account for geotechnical stability, dewatering requirements, and sequencing to ensure consistent ore supply to downstream processing facilities throughout the life of the mine.
