.4 Alternative methods of extracting metals

• The Earth’s resources of metal ores are limited
• Copper ores are becoming scarce and new ways of extracting copper from low-grade ores include phytomining, and bioleaching. These methods avoid traditional mining methods of digging, moving and disposing of large amounts of rock.
• Phytomining uses plants to absorb metal compounds. The plants are harvested and then burned to produce ash that contains metal compounds.
• Bioleaching uses bacteria to produce leachate solutions that contain metal compounds.
• The metal compounds can be processed to obtain the metal