People having trouble getting parking machines to accept $2 coins might want to check the date.
A slight variation in the metals used in the 1997 coins resulted in them being rejected by vending machines.
The New Plymouth District Council became aware of the problem with the coins after installing its new parking meter system in 2012.
Angus Barclay, Reserve Bank of New Zealand communications adviser, said the coins were withdrawn from circulation in January 1998 when the problem was first identified.
"These coins had gone into circulation just prior to Christmas but, unfortunately, some gaming and vending machines rejected them," Barclay said.
"The reason was a slight variation in the metals used, compared with older $2 coins already in circulation.
"This affected the coins' electrical conductivity, which is used as an authenticity test by many vending machines."
Barclay said fresh coins were minted were issued later in 1998 after extensive testing.
A total of 1 million faulty coins were minted but Barclay could not say how many remained in circulation.
District council customer and regulatory manager Mary-Anne Priest said the public alerted the council to the problem.
"We picked it up quite quickly because we were getting a lot of complaints from people that our machines wouldn't take the coins," Priest said.
The council contacted its parking meter contractor who confirmed there was an issue with the coins.
"My understanding is that, and I'm not sure 100 per cent where the information came from, but they were saying you can't use them in any vending machines at all," Priest said.
She did not know what the exact problem with the coins was.
"They must be just slightly different. It's just strange - for some reason, the machines just won't register them."
Judith Sewell-Monod, of New Plymouth, said she was unaware of the problem when spoken to by the Taranaki Daily News yesterday.
"Obviously I haven't tried to use one either," Mrs Sewell-Monod said.
THE $2 COIN
Alloy: Aluminium-bronze Diameter: 26.5mm Weight: 10 grams Edge thickness: 2.70mm Edge treatment: grooved Design: Kotuku (white heron)
*Have you ever been caught out by the 1997 $2 coin? Share your story in the comments section below.
- Taranaki Daily News
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