Stolen pounamu ranks as the commodity second most traded for drugs, after cash, according to a West Coast hapū.
Te Rūnanga o Ngāti Waewae Chair Francois Tumahai told RNZ that pounamu was used because "dealers recognise its value".
"They use pounamu to purchase drugs because it's accessible. People can access it from rivers or through mining, and that's just crazy."
Tumahai said if individuals knew how to identify pounamu on Te Tai Poutini (the West Coast), they can simply go down to the river, find it at their feet and take it, even though it is prohibited.
"We've done quite a number of raids with police, and we usually go along because there's pounamu involved in it."
"It's absolutely mind-blowing how much pounamu is being pulled out from drug raids. The last one we had was a trailer worth.
"When burglaries happen down the coast, TVs don't go walking, what goes walking is people's pounamu collection."
Pounamu holds deep cultural significance to tangata whenua in the South Island because it represents who they are as Poutini Ngāi Tahu, Tumahai said.
"Our tamariki are raised with an understanding of its significance and the knowledge of how to find and protect this taonga.
"We only exist on Te Tai Poutini because of pounamu, because that's what brought us here."
He said for centuries there had been many battles to acquire the kaitiaki (ownership) of pounamu.
"Every piece of pounamu is significant to us, it is us."
The rights to pounamu were officially returned to Te Rūnanga o Ngāi Tahu in 1997 through the Ngāi Tahu (Pounamu Vesting) Act.
But Tumahai said while they retrieved the rights, they did not get any "powers or compliance to go with it".
"We're at the mercy of government departments, police, customs, and similar entities to ensure they intercept pounamu when it leaves the country or to handle compliance on our behalf."
He said this was why it was important that iwi build strong relationships with government departments like Corrections and police.
"It is the only way currently that we can look at any hope of getting it returned."
In an emotional ceremony at the beginning of November, more than 60kg worth of stolen pounamu was returned to its rightful guardians Poutini Ngāi Tahu.
New Zealand Customs Service and 'Ngāi Tahu Pounamu' said this return was a part of an ongoing joint commitment to stop the illegal trade of New Zealand taonga.
Tumahai said they also had a growing relationship with police and that local officers have been doing "fantastic work" in retrieving stolen taonga.
"In the drug world on the coast, they know what's going on, they know there is pounamu involved."
Tumahai said once police operations were complete, local hapū and iwi stepped in to identify the stones' origins and retrieve the pounamu.
Inspector Tracey Wharehoka from Tasman District Police said: "Police have seized pounamu believed to be illegally obtained or held in a number of instances across West Coast and the wider Tasman District."
"Often pounamu is located at addresses where a search warrant is executed on an unrelated matter, and there is no reasonable or lawful explanation for its possession or ownership.
"It is likely that pounamu is used as payment for drugs or is an item traded in otherwise illegal activity."
But Wharehoka said: "How pounamu came to be in possession of someone can be difficult to confirm as among other reasons those located with it illegally in their possession are often uncooperative."
Wharehoka said pounamu was also identified and located when posted for sale on online marketplaces and through information reported by members of the public.
She said police worked very closely with iwi across the Tasman Police district, including in the protection of Pounamu.
"We have open lines of communication with local iwi to ascertain identification, possession, and ownership matters efficiently and effectively."
The relationship between local iwi, local organisations and other government agencies such as MBIE (Ministry of Business, Innovation & Employment) and police had been "positively growing," Wharehoka said, as they work alongside one another to "assist in areas of expertise involving pounamu".
Tumahai said carvers and purchasers of pounamu have a responsibility to ensure its authenticity.
He encouraged buyers to use the Ngāi Tahu Pounamu website to ensure the pounamu they purchased carried a mark of authenticity and a unique traceability code.
"This guarantees the seller is licensed and the stone has not been stolen.
"With this knowledge you can be reassured the stone has been treated according to our customs and carved with care."
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