At the time of writing, the maturing Grasberg Block Cave (GBC) is producing an average of 14,500 tpd from three active mining fronts. The mine is currently comprised of approximately 250 km of development with 42,000 m2 of established undercut from two production blocks beneath the Grasberg open pit. The pit to underground transition is ongoing under strict geotechnical control with a separation of approximately 175 m. Pit operations are expected to cease by the end of 2019 with breakthrough of the cave to pit in mid-2020.