It may be 10 years since we joined the euro, but the Central Bank of Ireland estimates that over €300m worth of punts are still unclaimed for. The majority of Irish households are likely to possess a long-forgotten jar of old coins and a handful of banknotes.
It would be worth taking a look at what you have because certain coins are commanding enormous prices. Take the 20p piece -- the copper-coloured one featuring the horse. If you find one of these from 1985, you stand to make at least €10,000 in auction.
That's because the coin wasn't officially introduced until 1986, and only a tiny number were produced the year before -- and only to vending machine engineers for recalibration. All were supposed to return to the Central Bank to be melted, but some slipped through.
It's the same story with a 1992 10p coin. The following year, a new reduced-sized 10p was officially unveiled. But early examples were specially minted for the vending machines and, if you come across one, your bank balance will swell by between €5,000 and €10,000.
"It's their very scarcity that makes them so collectable," says one of Ireland's foremost coin collectors and numismatic experts, Mike Kelly. "The fact that anomalies like those coins exist gets collectors really excited. I saw a 1985 20p coin a few years ago at one of our coin fairs and I knew what a big deal it was.
"People come to me with Victorian pennies and think they have a small fortune on their hands, but they don't because there are so many examples out there. Sometimes it's the coins you don't think much of that can be the very desirable ones. A 1938 penny is worth between €12,000 and €14,000."
Even contemporary currency can be worth far more than its face-value. "If you have a €500 note with a serial number T -- the letter for Ireland -- that's worth about €800," Kelly, who works in the electronics industry, says. "Some of the Series A banknotes -- the 'Ploughman' and 'Lady Lavery' ones that were used from the foundation of the State until the mid-1970s -- can command up to €5,000 if they are in a flawless condition."
But such prices are in the ha'penny place -- pun intended -- when compared to the 1933 "Double Eagle" $20 gold coin that will be on display in Dublin's Royal Hospital Kilmainham tomorrow and Wednesday. Admission is free. (see www.1933doubleeagle.ie).
Valued at $20m by London-based coin specialist Tim Banks, it is the world's most celebrated coin.
"It's effectively the coin that never was," according to Banks, the director of the Dublin Mint Office. "President Roosevelt ordered that all of these coins be melted down during the Great Depression and the handful that remain are in the ownership of the US Mint.
"The only example that was in private hands was sold at auction for $7.59m, but I've no doubt that the one we're exhibiting in Dublin [owned by the Smithsonian Institute] would command three times that amount were it for sale."
The Dublin Mint Office was established last year partly, Tim Banks says, as a result of the number of Irish people who had purchased coins from sister company, The London Mint Office. Both firms are under the ownership of Samlerhuset Group of Norway.
"Coin collecting has been a popular hobby for many centuries," he says. "We source coins from state mints, national banks, reputable coin dealers and auction houses across the world. We provide a wide range of the best quality coins from ancient to modern times, and from virtually every country."
One of the coins it is selling on its website is the commemorative Padraig Pearse 10 shilling piece, which was minted in 1966 as part of the 50th anniversary of the Easter Rising. The Dublin Mint Office's asking price is €129.
Mike Kelly, meanwhile, says this coin, which he describes as "one of the finest ever minted in Ireland thanks to its unusual concave design" changes hands at coin fares for far less -- "usually between €15 and €18".
Kelly's obsession with coin collecting began as a school-boy. He was intrigued that he could pay his bus fare with a myriad of different coins.
"It wasn't just Irish money that was accepted in those days, but UK currency too and coins from the Channel Islands and the Isle of Man," he says. "Then you start to notice that certain years are rarer than others and those are the ones you look out for."
He says a new generation is being turned on to coin collecting thanks to the euro. "There are so many EU member states and each of them has a different design on their coins. Factor in all the different designs and years minted and you have a huge number of different 1c or 5c coins."
The recession has also played its part with up to 500 hopefuls turning up each day at the Spring Stamp and Coin Fair at Dublin's RDS in early February. "There was huge interest because we were offering free valuations," Kelly says.
"People were hoping that they'd happened upon something valuable in their homes. Some of them came away with a few hundred quid, but most simply came away with the coins they brought and I'm hoping that some of them left the RDS with a whole new hobby."