Resource threshold It would take a lot more than 1 billiom lbs cu tp bring Rio back to the table . Consider they were looking for a Kansanshi size deposit . > over 1billion tons of ore . At 1% cu per ton would be 22 billion lbs copper . MINIMUM
Kansanshi has been in operation over 20 years and today still commands over 800 milliom tons of ore reserves
. They process 200,000 tons every day . That is what you call a generational mine Sherry.