The Dunedin accountant took his "coin and relic" metal detector to local beaches and mudflats whenever possible, in search of buried curios.
Once found, items remained an intrigue as Mr Auckram researched their history and local context.
"Some people say it's just a pile of junk but every little thing has a story. It all has local significance and I like finding things that are historic to the area," he said.
On Saturday, the first public exhibition of Mr Auckram's treasures will open at the Coronation Studio in Portobello.
Mr Auckram encouraged viewers to share their thoughts on where items may have originated and why they ended up underground.
Among his artefacts were pieces dating back to the early 1800s.
Musket balls were probably from the time of the Maori land wars, Mr Auckram said.
About five years ago, he had a stroke at work and had vowed to "ease back" a bit.
His passion for finding hidden knick-knacks intensified about the same time and he bought a metal detector.
"I've always been keen on treasure hunting, ever since I was a kid. I grew up in Auckland and was always searching for stuff, eeling in mangrove swamps or looking for golf balls in the middle of the night in golf-course creeks.
"I think I've got hunter-gatherer in my blood," he said.
Mr Auckram occasionally found modern coins, which was "a bonus", but he viewed metal detecting as a hobby rather than a way to make money.
He preferred beaches and mudflats because things could be easily dug up, and the earth replaced without hassle.
Metal buried in anoxic mud also preserved well, and Mr Auckram's old coin collection proved it.
This year to date, he had removed 25kg of lead from Latham Bay alone, mostly in the form of old sinkers.
Mr Auckram handed any jewellery to the police, and it was returned if not claimed.
His exhibition Sand Mine would be opened with a cup of tea and mudcake, and would finish on July 22.
