 The 2,575‑million-year-old Yellowknife greenstone belt in the Northwest Territories is the host for world-class gold deposits with total production of 15 million ounces of gold.In the Archean Hope Bay greenstone belt of western Nunavut, three large gold deposits have been known as Doris, Boston and Madrid, while the 2,677‑million-year-old Abitibi greenstone belt of Ontario and Quebec is the second most prolific gold producing area on Earth; the most prolific gold producing area is the Witwatersrand hill range in South Africa.Other magmatic formations, such as dike swarms and sills, are known to contain base and precious metal deposits.