What prices are being realised for stamps in Ireland and how might you go about estimating what your own stamps may be worth?

A recent Dublin auction of stamps and postal history, which fetched £30,000 overall (€38,092), is a good indicator of the kind of values being fetched by stamps at auction in Ireland. For instance, one collection of stamps from Argentina, comprising stamps from 1858 to 1970, sold at Whyte's of Marlborough Street, Dublin, on July 3rd for £2,400 to a Buenos Aires dealer.

You can look up stamp values in reference books such as the authoritative Stanley Gibbons catalogue. But the values given there may be considerably higher than that which owners would receive by selling their stamps, according to Mr Ian Whyte, director of Whyte's auctioneers.

For instance, an 1888 to 1972 collection of Canadian stamps was sold at the recent Whyte's auction for £1,300 to a Kildare collector. Mr Whyte says that if you added up all the prices for the stamps in that Canadian lot in Stanley Gibbons, it would come to more than £6,000 sterling. But in fact Mr Whyte fairly accurately estimated the lot at £1,200, just £100 less than it actually fetched.

"We estimated it at £1,200 so that's a lot less than the catalogue, but you've got to remember the condition might be a bit mixed. Most dealers are selling Commonwealth stamps at around about half catalogue, sometimes a bit less, sometimes a bit more. It also depends on whether the stamp is hinged or unhinged. . . But some dealers, you would see them charge only a tenth of Gibbons," he says.

The standard is there "but people work on percentages of it", considering the Stanley Gibbons valuation as retailers might regard a recommended retail price (they can and do sell below it. "But there are other factors that come into it. You've got to remember that things are second-hand so the nearer it is to perfect the nearer it's going to be to full catalogue."

That £6,000 plus sterling value could pertain "if everything in it was perfect", he says.

Stamp collectors are "very sophisticated", and they study catalogues in great detail, he says.

A single stamp, a black £1 Postal Union Congress 1929 in mint condition, described by Mr Whyte as "one of the most popular British stamps", was acquired at the recent auction by a Dublin collector for £600, which exceeded its estimate by £100. "But remember it cost £1 in 1929, which was a lot of money then," he says.

A set of eight misspelled "Erie Puist" labels, "forerunners" produced for propaganda reasons by American sympathisers after the 1916 Rising (although not valid stamps), sold for £340 to a collector in Wales, exceeding the £300 estimate. Had the eight not been split, they may have fetched £400 or £500. "Some of the Irish labels are the most valuable in the world," says Mr Whyte. One 1930 Shannon Scheme first-day cover sold to a Donegal collector for £550, while a second one went to a London collector for £600. That stamp is of particular interest because of confusion over the precise date of issue and its rarity.

But even relatively recent stamps can be valuable. A 1976 Irish 15p stamp celebrating the US Bicentennial, which had no silver printing on it, estimated at £400, sold for £500 to a collector in Saudi Arabia. "Eire" and its "15" pence value were absent from the stamps, and the astute original purchaser, having noted the error, immediately went back to the post office and bought the full sheet of stamps.