The Ngai Tahu papatipu runanga has formed a deal with mining companies where it pays miners half of an agreed value for any pounamu found in its territory.
Spokesperson Francois Tumahai says about 3500kg of pounamu - also known as jade - has been declared in the past six months, for which up to $45,000 was paid.
Ngati Waewae isn't sure how much more is being taken but believes there is a ripe black market.
Once the new arrangement is in place and more pounamu is returned, the price of it will go down and the black market won't be able to compete, which will be a win for the industry, Mr Tumahai says.
The agreement is about restoring the mana of the stone, he says.