Rapu-Rapu Processing, Inc. (RRPI) processes the lump ores extracted by RRMI.

Its base metal plant can process one million tons of ore, from milling to concentrating, into approximately 36,000 tons of copper concentrate and 26,000 tons of zinc concentrate as primary product. Copper contains 25% copper, 7% zinc, 30g per ton gold and 350g per ton silver. Zinc concentrate on the other hand contains 50% zinc and 5% copper. RRPI is the only zinc processing plant in the Philippines.

Its Cyanide-in-leach (CIL) plant produced silver and gold bars at the start of the project in 2005 but has now been de-commissioned.