In his 12 years as a plumber, Alif Babul has stumbled across all sorts of oddities and collector's items, but this one was worth more than all of them combined.

Babul and his apprentice, Dean Materi, were in the process of renovating a bathroom and had just ripped out the bathtub when they happened across it. 

"Lo and behold, there was a gold bar sitting there," said Babul.

Neither of them initially recognized the one-kilogram, stamped brick of gold worth more than $50,000 for what it was, and the gold treasure nearly ended up in the dump, he said.

"Who stores gold bars underneath their tub, right? Kinda crazy."

It was an amazing find, but not one for him to keep.

As per company policy, though not without a small degree of hesitation, Babul returned the treasure to the owners of the house. 

"My wife and I had a long chat about that. I said to my wife, 'I don't know if it's a good thing or a bad thing, but it's the right thing to do.'"

The owners, who had lost track of the brick's whereabouts, were understandably delighted, said Babul.

"Hopefully karma comes our way. Good karma," he laughed.

Alif Babul Dean Materi

Alif Babul (left) and Dean Materi returned the brick to the original owners, as per Perfection Plumbing & Gas Ltd.'s company policy. (Supplied)