John Walsh and the crock of Potter gold

What do you do if you find a priceless treasure - a proof copy of JK Rowling's first book - on your shelf? Sell it, thought our man. Well, that was the idea...

It was not a terribly prepossessing object. A 224-page book, bound in stiffened blotting paper, its cover pristinely white with a band of gold across the middle. I could have been holding an unfeasibly thick lemon curd sandwich. It was small and light and inconsequential-looking, and the legend "Uncorrected Proof Copy" was a reminder of its ephemeral status. But in the middle of the smear of yellow, like the secret at the heart of a crock of gold, were these few precious words:

It was not a terribly prepossessing object. A 224-page book, bound in stiffened blotting paper, its cover pristinely white with a band of gold across the middle. I could have been holding an unfeasibly thick lemon curd sandwich. It was small and light and inconsequential-looking, and the legend "Uncorrected Proof Copy" was a reminder of its ephemeral status. But in the middle of the smear of yellow, like the secret at the heart of a crock of gold, were these few precious words:

"J K Rowling - Harry Potter and the Philosopher's Stone".

I was standing on a chair at the time and damn near fell off it. I'd been having a clear-out of the bedroom bookshelves, a cull of proof copies. Proofs - sent out to alert the book trade and the literary editors to "significant" new titles - are not objects of beauty. They curl up and fade and get dog-eared and you wouldn't want them on your shelves between the posh £20 hardback biographies. You throw them out after a while and never miss them.

But this was different. This was a potential goldmine. Like the picture of Professor Dumbledore of Hogwarts School holding under his arm the Bible of wizardry, I held in my hand the world's favourite book - the début work by the world's favourite author - in an edition even scarcer and obviously more valuable than the first edition. Yikes! Riches!

The children came to look. They noted my trembling fingers and bleach-white cheeks as I explained what I'd got. "Can I see it?"asked the five-year-old, extending several tiny, Nutella-smeared fingers. " Don't touch it!" I yelled. "The tiniest blemish and it will no longer be worth, ooh, ten thousand quid."

"I hate to tell you Dad," said the eight-year-old, "but there's something wrong with Chapter Two. It's called 'The Vanishing Glass' not 'The Vanishing Grass'. And they've spelt her name 'J A Rowling' on this page. They must be stupid."

"And this cover's different," said the eldest. "The actual cover's got more red here and more blue there. Does that matter?"

"Matter?" I shrieked. " Matter? It's much better, my darlings, if the thing's covered in mistakes. It's like having a Penny Black with the nose in the wrong place." The children looked at each other. There was no fathoming the world of grown-ups.

What do you do when you find a priceless treasure in your bedroom? You ring your friends and swank about it. "Blimey," said Chris. "I know first editions of the Philosopher's Stone go for five figures in America. And this is even earlier. Drinks on you from now on, old boy." A friend who's a children's-author's agent knew about the proofs. "You've got one of 200 readers' copies sent out by Bloomsbury in March 1997. I know someone who sold a copy just like yours for $5,000 to a guy in Beverly Hills."

My heart leapt.

"It was a bit dog-eared and worn and the spine was broken and there was a coffee-mug stain on the cover..."

And it was still worth $5,000? My heart bounded like a terrier.

"...but it did have a warm personal inscription from Joanne Rowling inside."

Oh drat.

Emboldened, I went to the heart of secondhand-book land in London. I e-mailed Maggs, the legendary antiquarian booksellers in Berkeley Square. Would they like to see it? Ed Maggs himself replied.

"You're right in suggesting that we don't do Rowling," he said. "Good as the books are, it's far too flaky a market for us to be involved in, but there are plenty of people who disagree."

He suggested a couple of dealers. I wrapped my treasure in a blue plastic folder and high-tailed it to Cecil Court, off Trafalgar Square.

In Nigel Williams Rare Books, a lady in black with bare arms, lots of jewellery and a reckless décolletage explained the dealers were all busy elsewhere, and the shop didn't dish out ad hoc valuations just like that, and anyway - I shyly revealed the transparent blue folder.

"But yes, that is interesting" she breathed. "One moment." Soon she had a chap on the phone explaining that they dealt with real books, 19th- and 20th-century first editions, thank you very much (the jewel of their catalogue is Charlotte Bronte's The Professor, 2 vols. original cloth, small stain on flyleaf, £4,000). And they didn't deal in proofs. "For every 20 colectors who want the first edition, there'll be one who wants the proof - and we have no customers for the proof at the moment." He suggested I try Sotheby's and a dealer in Kensington.

Dispirited, I moved down Cecil Court to Bell Book & Radmall, the first-edition specialists. The owner, James Tindley, looked on with interest, as I exposed my ur-Rowling like a slow-motion flasher. Then he and a colleague began the traditional, antiphonal exchange known in the book trade as "talking it down".

"These proof copies aren't really the point, are they, Adam?"

"It's the 350 hardback firsts that people want, James".

"They're the ones that really sell."

"Fifteen thou for a first edition. Dollars of course. Silicon Valley's where the real money is."

"It's a matter of reading age. The average US millionaire is 24, and he's only read three books in his life."

"And two of them are by Tolkien."

Er, about my proof copy...

"The age of the proof is over," said James gloomily.

"Proof copies are dead here," said Adam. "Their heyday was 12 years ago."

"Fifteen."

"Now you can't give them away. Okay, Brighton Rock, proof of that you'd get £4,000, but since you're talking £25,000 for a first in a dust jacket, you'd expect a proof to be half that..."

"People don't want them, though."

"Nobody cares."

It was like Waiting for Godot. I felt like apologising for wasting their time on such a piece of ordure.

"I could phone a man who might buy it off you," said James kindly.

No, please don't trouble, I said. I'll just see myself out and - "He'd give you a grand for it".

A thousand quid! After all the talk, it was surprising that anyone could be interested. It was miles off the vast wedge of money I'd hoped for. But it was a start.

Next I headed for R A Gekoski Rare Books and Manuscripts near the British Museum. Rick Gekoski is an ebullient, wavy-haired American with an impressive store of knowledge about writers' lives. He displays immaculate literary taste (his list concentrates on the Premier League of Lawrence, T S Eliot, Joyce, Beckett, Wilde, Graves, Conrad, Durrell, Larkin and Huxley) and mildly alarming fetishes: at the least provocation he'll show you a hank of Sylvia Plath's hair, a "first cutting" when the poet was two and a half (it's in his catalogue priced £2,500). "I've just bought Joyce's deathmask," he announced proudly. "I'm going to cast it in bronze, make nine masks, and see what happens."

He knew all about the Potter proof copies ("I've heard of them selling up to $7,000 in California") but wouldn't commit himself to buying. He might just pay £2,000 and pass it on to the trade for £2,500. "But I wouldn't catalogue it, or put it on our internet site, or be seen to be dealing in it." Why? "Because it encourages a kind of lunacy. I don't like participating in a market where I think money is being spent foolishly." Even if it made you a small fortune? "It's a matter of value," said the high-minded Gekoski.

"For the price of four Harry Potter first editions, you could build up a substantial Conrad or Beckett collection."

I learnt (at last) what Potter books are worth on the open market. The exciting stuff is the first edition. Only 350 (a tiny print run) came out in hardback and collectors are paying £10,000 for them. £14,000 is the highest reputed figure, though a set of four Potters, all firsts, went in New York for $24,000.

Joanne Rowling's signature conveys instant cachet. She signed at least 3,000 copies of the fourth instalment, Goblet of Fire (from a one-million print run) and American collectors are buying them up at £500 a time (so hurry).

Gekoski did, however, steer me towards the biggest Harry Potter dealer in town, Adrian Harrington, who runs a bookshop in Kensington Church Street. Summer flu had confined him to a back garden somewhere in Kent, so I sat outside a bar in Pied Bull Yard, nursing a spritzer, mobile phone clamped to ear, and got a lecture from the Mr Big of Hogwartsiana.

"The world of books hasn't seen anything like the Harry Potter phenomenon before, which is why you'll find prices are all over the place.

It's absolutely the right book at the right time, just as the world is ready for the new Tolkien. Have you noticed how these things go in 30-year cycles? Lewis Carroll in the 1860s, Arthur Rackham in the 1900s, Winnie the Pooh in 1926, then Narnia and Middle Earth in the Fifties, then Roald Dahl in the mid-Seventies, now J K Rowling? She's taken Tolkien, C S Lewis, Greek myth and pagan magic, everything from the world of folklore and mythology, and made a single entity of it. The plot is Just William goes to the Chalet School. There's even a bit of Dennis Wheatley in there."

Did he ever sell Potter proof copies? "Oh sure," said Harrington airily. "I've just sold one for £4,500. If yours is in mint condition, I could pay £2,500 for it."

I blinked. Did the secondhand book trade often charge a mark-up of 80 per cent? "It's a volatile market," he said. "Two months ago it had gone a bit quiet. The the Goblet of Fire came out, and it's complete madness at present. In a couple of months it'll calm down for a while, then the film will come out..."

If it's bound to increase in value, Adrian, (I said) perhaps you could afford to be more generous? "Oh - if I had it in my hand right now, I might go to £3,000."

Back home I approached the internet, which, as everyone will tell you, has several auction sites to help you cut out the Harrington and Gekoski middlemen. Amazon.com, the mega-bookseller site, has a link-up with Sothebys auction house, and its admirably clear instructions guide you into writing a cogent and not-too-boastful sales pitch. The alternative is ebay.com, which is more down-market ("more Exchange & Mart than Christie's," a friend explained), and then you're into some weird territory, like a "collectors' corner" at www.abebooks. com, and a collectors' website called uncorrectedproof.com. I've done them all: I've stuck my vainglorious little advertisement on half-a-dozen cyber-noticeboards, and I'm still waiting for a reply, 48 hours later. It doesn't compare, I assure you, with hanging out in the shops where Rick, Adrian and Adam and their peers in the trade drift in and out, swapping information about the byways of literary history and gossiping about wildly extravagant bids at auction.

I've still got the modest white-and-yellow proof in its little plastic folder. It was worthless, then worth £1,000, then £2,000, then £2,500, then £3,000. I might just wait a week, to see what the websites bring, or a month until the movie goes into production, or a year until Harry Potter V is published. Hell, I might have done anything had not a colleague pointed out the small print on the back: "This is an uncorrected proof copy," it reads, "and is not for sale."