An alleged fragment from the Pink and White Terraces is up for sale
A 10cm-long chunk of New Zealand's history is being put under the hammer, its seller claims.
A rock fragment supposedly belonging to the Pink and White Terraces is being auctioned on Trade Me, with the starting bid set at $500.
Previous sales of rock from the famed terraces has drawn international attention and commanded prices in excess of $60,000.
But already questions have been raised over the sale item's authenticity, with one scientist urging would-be buyers to do their research.
And a Maori scholar says if the rock is authentic, then its sale could breach Maori protocols.
The rock seller, who hasn't responded to media requests for comment, said the collectible has been in his family's possession for five generations.
To put buyers' minds at rest, the family are happy for the rock to be tested to establish its authenticity.
The online auction closes at 10am Sunday.
The Pink and White Terraces were once considered the eighth wonder of the world and attracted sightseers from around the globe.
They were thought to be destroyed by the 1886 eruption of Mt Tarawera.
GNS scientist Cornel de Ronde said it would be difficult to establish whether the rock was authentic.
The best way to prove the rock was from the famed terraces was for the seller to produce photographic evidence.
"It's possible that scientists from GNS could help validate the authenticity of the sample but we would need to set up the protocols and template for that and currently there hasn't been the funding to allow that work to happen," de Ronde said.
"Ideally, you'd have a photograph of the seller's great, great grandmother holding the piece, and the shape can clearly be made out, and hopefully she is standing in front of the terraces. That would give you 100 per cent certainty but those photos are rarer than hen's teeth."
June marked 130 years since the eruption of Mt Tarawera in 1886.
In 2012, two pieces of the Pink and White Terraces were bought for $64,000 by a private buyer at an Auckland art auction.
The pieces, which attracted interest from around the world, were collected by 15-year-old Ina Haszard a year before Mt Tarawera erupted.
De Ronde said a number of tests could be done on the rock to ascertain its age, such as carbon dating organic material encased in the rock.
"This issue has raised its somewhat ugly head a few times in the recent past and there needs to be work done so we can test these samples and give people a probability of whether it's real or not."
Waikato University's Professor in Te Reo and Tikanga, Pou Temara, said he was interested to know the background of the rock seller, saying if they were Maori "then they should know better".
"They should know that with the passage of time, the tapu of Tarawera still holds," Temara said.
"If that were not true, then we wouldn't hold our ancestors and our sacred places in such awe."
However, Temara said if the rock was authentic, then its tapu nature had to be balanced against the long passage of time since the eruption.
"When we go overseas, people bring back rocks from Gallipoli where people have died, so is that rock tapu? You have Maori people who do go to Gallipoli and come back with these rocks so if it's good for the goose, it's good for the gander."
Te Papa spokeswoman Ellie Campbell was not able to confirm if the museum had any Pink and White Terraces fragments in its collection.
It's estimated the Pink and White Terraces were formed over a 600 year period, after an eruption in 1314.
The terraces would have been made mostly of silica. The silica released through the Earth's surface formed in steps.
The white terraces covered three hectares. The pink terraces were about half that size.
The Mt Tarawera eruption lasted about five hours and is considered the largest volcanic eruption in New Zealand in the past 200 years.
Numerous Maori villages were destroyed, including the famous Buried Village tourist attraction near Rotorua.