Drift mining is a type of underground mining where tunnels, called drifts, are driven horizontally or nearly horizontally into the side of a hill or mountain to access an ore or coal seam. The entry or access point of a drift mine is typically above the water table and on a slope, allowing direct horizontal access to the mineral deposit without digging vertically downward.
The term “drift” refers to these near-horizontal passageways that follow the mineral vein or coal bed. A drift may or may not intersect the surface, and it differs from other mining tunnels like crosscuts (which intersect veins) or levels (which may do either). Drifts serve multiple purposes, including mineral extraction, haulage, ventilation, and exploration.
Drift mining is commonly used for relatively shallow mineral deposits exposed on a hillside and is considered more economical and simpler than vertical shaft mining because gravity can aid in removing mined material. It has historically been applied to mining coal, gold, quartz, zinc, and other minerals accessible near the surface or outcropping.
Due to its horizontal orientation, drift mining was historically less safe in some cases, particularly with water ingress risks, which limited its use compared to other methods.
In summary, drift mining involves creating horizontal tunnels into mineral seams from a hillside to extract ore or coal without descending via a vertical shaft, making use of natural topography for access and material removal.
