Located a few miles South of Lake Argyle. A diamond-bearing lamproite pipe discovered by Ashton Joint Venture in 1979. Open-pit mining began in 1985.
Argyle's production consists of 5% gem and 70% near-gem stones, with the remaining 25% being industrial diamonds. The mine also produces between 90% and 95% of the world's pink diamonds.
Refs.:
http://www.mining-technology.com/projects/argyle/
http://www.infomine.com/minesite/minesite.asp?site=argyle