Definition of quarry

A quarry is a site where stone, rock, sand, gravel, or other non-metallic materials are extracted, most commonly by open excavation at the Earth’s surface. Quarrying is typically associated with the production of building stone, slate, limestone, chalk, sandstone, granite, and aggregate, and differs from mining in that the material is generally used directly or after simple processing, rather than being smelted or chemically refined. Quarrying has been practised since prehistoric times and has played a major role in construction, infrastructure, and landscape development.

While quarries are usually open workings, some forms of quarrying—most notably slate extraction—extend underground. In these cases, extraction may follow dipping beds or veins into hillsides through adits, chambers, and galleries, creating extensive subterranean workings that resemble mines in form. Despite this, such operations are traditionally and technically still referred to as quarries, reflecting the nature of the material extracted and the methods of working large, laterally continuous stone bodies rather than discrete ore deposits.

In geological and heritage contexts, the term quarry also includes abandoned and historic workings, whether open or underground, that preserve evidence of past extraction techniques, tool marks, and industrial infrastructure. Many former quarries are valued for their geological exposures, fossil content, or industrial archaeology, and are frequently repurposed for education, recreation, or nature conservation.