Tarkwa is noted as a centre of gold and manganese mining. Tarkwa Mine, which is a large open-cast gold mine, is situated to the northwest of the town, and Nsuta manganese mine is situated to the east of the town. Tarkwa Mine mines several low-grade conglomeratic "reefs" of Tarkwaian type. These reefs are of mid-Proterozoic age. Tarkwa Mine currently (since 2007) has the distinction of being the largest gold mine in Akanland. Approximately 24 tons of gold is produced annually, and 100 million tons of earth is moved to achieve this production rate. The Tarkwa Goldfield was discovered a few years before the Witwatersrand Goldfield in South Africa.