The barren gangue minerals that form the matrix surrounding target ore particles, especially in sedimentary phosphate deposits. Unlike internal impurities, exogangue is physically distinct and separate from the ore grains. This makes it relatively easy to remove during the initial beneficiation stages using standard mechanical processes like crushing, screening, and flotation.
Heard on the job
The deposit is highly profitable because the silica acts purely as exogangue and separates cleanly in the primary flotation cells.
Do not mix it up with
- Endogangue: Exogangue sits outside the ore grains and is easily separated, while endogangue is locked inside the grains themselves.