Sweeping his metal detector back and forth, Andrew Stavely recognised the signal immediately - and knew he'd found something.
He'd found a lot of gold jewellery during his time detecting but this would be his favourite find - a World War II soldier's dog tag.
"I was able to track down the family with some help of the group and we had that returned to them in Texas in America.
"We sent a note through to a guy I know from another detecting group in America, he went and knocked on the family's door and said: 'Hey, look this guy in New Zealand has found your grandad's dog tag and wanted to return it to you'.
"The family was pretty grateful, they sent back a nice note and a picture of the soldier, that was pretty cool."
The Rotorua metal detecting scene will be hoping similar successes result from the second annual metal detecting rally next weekend.
Event organiser and founder of Metal Detecting New Zealand Aotereoa, Stavely said around 50 people turned up to last year's event, but he expected a lot more this year.
"It's sort of a promote the hell out of it and cross your fingers and hope a lot of people show up. We've got a couple people coming up from Christchurch for it, and a guy travelling up from the Marlborough Sounds," Stavely said.
Stavely founded the Metal Detecting NZ Aotearoa Facebook page around five years ago.
"I was watching Youtube videos and I noticed there's large scale (metal detecting) events going on in every other country, apart from New Zealand. I thought I've got this social media platform, why don't I do the same thing you know?
"It's blown up into a pretty decent sort of tight-knit metal detecting community," Stavely said.
The group now had close to 700 members.
"One of the things I quite like is there's a lot of people that go through hard times and they join up in the metal detecting New Zealand community and it helps them pull through," Staveley said.
Stavely has been a keen metal detector user since 2010.
He said members were encouraged to respect the areas they were sweeping.
"We push a pretty strict code of ethics to leave the place as it was when we found it, we always take our rubbish and use custom tools to be less intrusive to the ground."
•The second annual metal detecting rally is on this Sunday from 11am until 4pm at Tikitapu (Blue Lake) in Rotorua. The event is child-friendly and free of charge.