i think you'll find lihir has a hell of a lot more than "18mt at 2.87g/t" think thats a mis-print. Just off the top of my head i'd say lihir island is one of the biggest goldmines in the world, producing 800,000 ounces p.a.
Robust will be doing well to find 800,000 ounces let alone have enough reserves to produce that p.a.
Just think you're getting a little carried away.