Fact of the day: it took Robert Friedland's Ivanhoe Mines and Turquoise Hill Resources 161 duster holes to find Rio's Oyu Tolgoi.
On the 162nd hole they hit the jackpot
https://x.com/paddygall1/status/1816095204455149771
This video is 12 years old and shows how difficult it can be to bring a very large mine into production (scheduled for 2015)
https://youtu.be/UoY5cVIdVMU?si=_YyiOgbQ_FWoZCqk