extraction
Porphyry ore at half a percent copper is crushed, ground and floated to a 25–30 % concentrate, flash-smelted to matte, converted to blister and electrorefined to 99.99 %; gold, silver, selenium and tellurium come out of the anode slimes. Oxide ore skips all that: heap-leached with sulfuric acid, then solvent extraction and electrowinning (SX-EW) straight to cathode.