Boxes of core, possibly chips, petroleum petrographic sections, and rock samples stored in the basement of Avalon, NIC, Wairakei, and Dunedin. It includes core materials from programmes going back to the 60s to present.

New Zealand's National Petrology Reference Collection contains rock and mineral samples from the earliest days of the Geological Survey to today. The collection is the single most comprehensive collection of New Zealand rocks and minerals in the world, and is a valuable national resource. The collection includes samples from on- and off-shore New Zealand, Antarctica and the rest of the world. It is added to continuously, and can be searched online using the PETLAB database (http://pet.gns.cri.nz). The contents of the collection include hand samples, thin sections, mineral separates, core cuttings and more.