An auction house has received thousands of calls and emails from around the world as a result of plans to sell a rare 20p piece worth thousands of euro.

Whyte's Auctioneers is selling a rare trial coin, now worth up to €6,000, which is dated 1985 and was issued in advance of production to various companies and organisations so they could calibrate vending machines and other coin-operated devices.

Sources at the Central Bank said fewer than 50 of the 500 or so pieces issued were not returned.

To date, about 10 examples in private hands have been recorded, making it one of the rarest Irish modern coins, even scarcer than the 1943 florin.

But since announcing the sale six days ago, the auction house has been swamped with people thinking they have one too.

Disillusioned

"It's been non-stop with people contacting us not only in Ireland but from abroad as well saying they have such a coin," said a Whyte's spokesperson.

"In one day alone we received at least 100 phone calls and scores of emails.

"There has been little time to deal with anything else.

"However, some people are getting carried away with themselves insofar as they think any of the 20p coins from 1985 onwards are worth thousands of euro, which they aren't. They specifically have to be the year 1985.

"We just don't want members of the public to be disillusioned and disappointed when they make contact to say they have such a coin. We would urge them to look closely at the year on the coin before they jump for joy.

"So excited have the public become that they are now asking us about other coins they have which they are hoping are worth a lot of money too."

The auction takes place on April 6 at 11am in the Freemasons' Hall, Molesworth Street, Dublin.