KEVIN Lowndes was feeling pretty guilty that he didn't tell his sister-in-law to take off her jewellery before entering the water.
Amanda von Roden was snorkelling on Thursday with Mooloolaba business Scuba World when she came out of the water in a panic.
Skipper Mr Lowndes said she was distraught as she had lost her wedding ring.
"She felt a bit devastated as you could imagine," he said.
But quick thinking led Mr Lowndes to mark on the GPS roughly where she had come up so they could search later for it.
With Mrs von Roden on a plane back to Germany, without her wedding ring of 20 years, Mr Lowndes took another planned snorkelling trip out the next day.
"But we took some divers from our club members also in hope that they would be keen to find it."
Four members including Roxanne O'Donnell plunged in the water to search.
After 34 minutes of diving Mrs O'Donnell came up with the ring in her hand.
She said that it was caught in a crevice and was lucky to find it.
"It was literally a needle in a haystack," Mrs O'Donnell said.
"When we were diving there was a lot of rubble and stuff on the ground and it was moving with the swell."
A chance encounter with a Wobbegong Shark got Mrs O'Donnell to turn around and she then spotted the ring.
"I felt pretty ecstatic to find it," she said.
"I nearly lost my ring once, don't tell my husband but, yeah I would feel so relieved if that was me."
It was found about 6 to 7m under water in a section that Mr Lowndes said not many divers go.
"A lot of snorkelling goes on there but you would never see it if you were snorkelling," he said.
"I appreciate the club members giving up their time to come out and look for the ring."
The ring will be returned to Mrs von Roden when Mr Lowndes and his family visit later this year.
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