In fact, you can use some pretty old stamps if you wanted to. ... If your old first-class stamp is, say, 30 cents, you’ll need to double up to get your letter to its recipient.

These tiny imperfections, once seen as flaws, can increase a stamp's rarity and valuation. So before you toss that old stamp collection, take a close look — you might be holding a piece of history.

A freelance reporter in London tries to sell his boyhood stamp collection and takes a journey through memory and vanished nations.