Sand claimed to come from the famed Pink and White Terraces, with a price tag of more than $1 million, has failed to sell on an online auction site.
The Pink and White Terraces were promoted as a tourism wonder before being destroyed during the 1886 eruption of Mt Tarawera near Rotorua.
Scientists last week announced they had discovered remnants of the Pink Terraces at the bottom of Rotorua's Lake Rotomahana.
The online auction closed night after reaching a bid of $1,001,700 but the sand failed to reach its reserve.
Trade Me spokesman Paul Ford told NZPA although the auction had expired, the seller could re-list the vial.
However, people should always bid with care especially when a large amount of money was at stake.
"If you're going to be bidding over a million dollars on something and you're just going to do that frivolously then you need your head read, I think."
Trade Me had spoken to the seller but it was not their role to confirm the authenticity of the sand.
"We're not geologists so it's pretty tricky from our perspective so we'd encourage people that are geologists to ask the hard questions of the seller and if the answers aren't satisfactory, don't bid."
The site watched high-profile auctions very closely and often rang bidders to check they were genuine, he said.
The seller's listing claimed the sand was taken from the Pink and White Terraces before the eruption.
They said their grandmother had given them the sand, which would be "subject to authentication" for any genuine bidder.
The page had 13611 views and has now expired.
Meanwhile, another seller, from Marlborough, is also offering vials of sand, apparently from the Terraces, but for a much lower sum.
The starting bid is $108, with no reserve, and the seller admitted its authenticity was unconfirmed.