Ventifacts have been mistaken for everything from adzes to pieces of shattered asteroid. The rocks, stones, and sometimes boulders, get their interesting shapes from being sculpted and polished over thousands of years by exposure to wind-driven sand.
The study of the provenance and the shape of the rocks sheds light on the past but they are also worth something commercially.
In the '70s, the Geological Society of New Zealand became concerned that people were taking trailer loads of the ventifacts away and selling them, and wanted to put a stop to it to preserve them. It's now illegal to take ventifacts from the Nukumaru Domain, to protect them for future generations.
Professor Vince Neall, an expert on the geology of the Taranaki region, says studies of these sorts of materials will continually be enhanced with new methods of geochemical analysis of isotope ratios.
"I find it stunning that we can now figure out what people have been eating in the past by studying the isotope ratios in their bones as to whether they were eating fish or whether they were eating meat," Neall said.