The research, by University of Otago emeritus professor of geology Dave Craw, is the first in the world to present photos of beach gold anywhere in the world.

He said the metal had been “mostly overlooked” during New Zealand’s gold rush years in the 1800s.

“The point of the study was to look at this horribly fine-grained stuff that nearly everyone ignores at the beaches around the South Island,” Craw said.

“There has been some mining (West Coast) but saving the fine gold is really hard for the miners,” Craw said.

But don’t pick up your pan yet. The research involved using an electronic microscope to capture the images.

The evidence suggests that in one Southland site, there were particles as small as 10 micrometres wide – a fifth the width of a human hair.

“And it is unlikely that people will see any,” Craw said.

“Even with a gold pan, the fine gold floats on the surface tension of water and a lot of it is lost.”