Freeport-McMoRan shares jumped early Tuesday as the company detailed a multiyear plan to ramp up copper and gold output following a deadly mud rush at its Grasberg mine in Indonesia. The move lifted the S&P 500 stock near a key support level. Seven Freeport-McMoRan employees died in the Sept. 8 incident, which the company said was unprecedented in the mine’s 40-plus years of operations and for which its says there were no warning indications.