| Iron Quadrangle | |
|---|---|
| Stratigraphic range: Paleoproterozoic ~ | |
 Geologic map of the Iron Quadrangle | |
| Type | Mining district |
| Unit of | Minas Supergroup |
| Underlies | Itacolomi Group |
| Overlies | Rio das Velhas Supergroup |
| Area | 7,000 square kilometres (2,700 sq mi) |
| Lithology | |
| Primary | Pegmatite, granitoid |
| Other | Itabirite |
| Location | |
| Coordinates | 19°54′S 43°12′W / 19.9°S 43.2°W |
| Region | Minas Gerais |
| Country | Brazil |
| Extent | São Francisco craton |
  Iron Quadrangle (Brazil) | |
The Iron Quadrangle (Portuguese: Quadrilátero Ferrífero) is a mineral-rich region covering about 7,000 square kilometres (2,700 sq mi) in the central-southern part of the Brazilian state Minas Gerais. The area is known for its extensive deposits of gold, diamonds, and iron ore, being the source of approximately 40% of all gold produced in Brazil between the years 1500 and 2000. The deposits themselves pertain to the Minas Supergroup, a sequence of meta-sedimentary rocks initially formed in the Paleoproterozoic, about 2.5 Ga. In the 2010s, there have been two collapses of large tailings dams, which caused extensive damage and loss of life.