Mines

Since the beginning of civilization people have used stone, ceramics and, later, metals found on or close to the Earth's surface. These were used to manufacture early tools and weapons. Flint mines have been found in chalk areas where seams of the stone were followed underground by shafts and galleries. The mines at Grimes Graves are especially famous, and like most other flint mines, are Neolithic in origin. Other hard rocks mined or collected for axes included the greenstone of the Langdale axe industry based in the English Lake District.

Today's mining techniques are divided into two common methods of extraction, surface mining and sub-surface or underground mining. Two categories of materials mined are placer deposits and lode deposits. Placer deposits consist of valuable minerals like gold contained within river gravels, beach sands, and other unconsolidated materials. Lode deposits, are minerals found in veins, in layers, or in mineral grains generally distributed throughout a mass of actual rock. Both types of ore deposits are mined by both surface and underground methods.