Graymont owns and mines New Zealand’s largest single lime quarry at Oparure, just North of Te Kuiti on the North Island. This 67-hectare quarry is located on top of the rich Waitomo strata and produces exceptionally high-grade limestone to supply the Company's Otorohanga and Te Kuiti Plants.

The Oparure plant, which predominantly supplies custmers across the North Island, also manufactures a range of high-quality pulverised Limestone products such as Aglime, Calcimate(R) and industrial fine lime in bulk, sacks and paper bags,as well as aggregates in bulk.