The colourful stamps, from Rome and the Vatican, were like ''small snapshots of her life'' to a five-year-old, and piqued an interest in geography, coins and postal memorabilia.

After finishing an economics degree, and working briefly for a major bank, Mr Shields decided to quit the world of banking finance and ''do something I was really passionate about''. He opened a stamp dealer's shop in Melbourne.

But if you're thinking stamp dealing would be a nerdish, sedentary business with more than its fair share of slow days, you'd be well wide of the mark.

This weekend, Mr Shields is in Canberra for a national stamp show celebrating the 80th anniversary of the Philatelic Society of Canberra.

Then he's off to a stamp auction in Perth, and will also be helping his business partner, brother Gary Shields, prepare for two major stamp shows in Asia. He's also a regular on Melbourne talkback radio, advising listeners on philatelic collectables.

''We generally do, on average, about 10 shows a year in Australia. We used to do the big stamp shows in London and Tokyo every year, but the dollar is too strong at the moment to make those trips worthwhile,'' he says.

His speciality is Antarctic philately (stamps, postcards, postal stationery) and this weekend's Canberra stamp show is showcasing the centenary of Sir Douglas Mawson's polar expedition. Such is the global demand for polar postal memorabilia that Mr Shields recently sold several items to a keen collector in the Czech Republic for $30,000. At the Canberra show, he has a rare letter ($9500) from Robert Scott's polar expedition in 1901, and postcards ($1500) issued to raise funds for the Mawson expedition.

Forged stamps are also keenly sought collectables, and can be double the price of the original stamp, especially if they're the work of Jean de Sperati - an Italian forger known as ''the Reubens of philately''. One of his most famous forgeries was Australia's first stamp - known as ''the kangaroo and map'' to collectors. Depending on its condition, a Sperati forgery of that stamp can sell for around $6500.

''Canberra has some very discerning collectors, and there are some incredible collections in this town. What's the appeal of stamp collecting? It's like having your own little history museum, that you can take out and look at any time.''

Canberra Stamp Show 2012 is open today at tomorrow, from 10am to 6pm at the Hellenic Club, Woden.