MAYBE one day I will be the person quoted in the newspapers saying: “It came from a car boot sale, and I almost threw it in the bin.”

Or: “I’ve been using this old boot sale pot as a waste bin all these years - is it really an ancient Chinese vase?”

How many time has this sort of thing happened? Too many.

In the latest instalment of car boot-find news a ‘shocked pensioner’ discovered that a diamond she ‘almost threw in the BIN’ during a home clearance is 34-carat stone worth £2 million.’

The woman ‘did not know where she acquired the diamond, but told the auctioneer that she ‘always visited car boot sales and bought trinkets’, so it was likely that that was the source.

Where are these car boot sales that generate such things? The ones where you can unearth eye-wateringly stunning diamonds, genuine Picassos and centuries-old Persian rugs?

I’ve been to many car boot sales, rummaged through countless piles of clutter and discovered some lovely things alongside all the tat, but nothing I would rush off to Sotheby’s with.

It’s not at all easy to find valuable items on sale at car boots. In my experience car booters are generally quite astute when it comes to what they stick in boxes to haul along on a Saturday morning. They tend to know what’s Antiques Roadshow material and what’s not.

It’s like some charity shops, which nowadays have staff trawling through Miller’s Collectables and placing the valuable donations, all priced accordingly, in locked glass cases which shoppers can see but need permission to handle.

What is more annoying than the lack of antiquities to be had for one or two pounds is the offhand, dismissive way people who claim to have come across these valuable items at car boot sales or in charity shops, talk about them.

They have almost always been on the verge of chucking away the 18th century Venetian glass decanter or the first edition King James Bible in the recycling bin, or sticking it in a charity bag. But somehow the item always ends up under the hammer at a top auction house.

“The lady came in with a bag of jewellery as she just thought she would bring it in as she was passing because she had another appointment in the town,’ said the auctioneer when asked about the £2million diamond.”

I don’t believe that anyone would take anything along to be valued by an expert without the slightest notion that they might make a mint out of it. You only have to watch those people on Antiques Roadshow, who are clearly crestfallen when told the antique they took along is a cheap copy of an original.

“I thought it might be,” they say. No you didn’t, we viewers yell.

I am sure there are still some bargains to be had at car boot sales, but they will be few and far between. The main reason for that is that nowadays everyone is an expert as to what to look for.

With so many TV programmes telling us how to find cash in the attic, loot in the loft, and millions under the mattress, it’s not surprising that we are alert to the bits and pieces that could make our fortune.

I’ve peddled my wares many times at car boot sales but never come close to allowing a genuine Matisse to slip through my fingers. That could be because I don’t actually own one, but if I did I can say for certain that it wouldn’t end up on sale for £2 in a muddy field.

The amazing car boot diamond will go up for auction at the end of this month. Maybe I’m just consumed with jealousy. Yes, quite frankly, I am.

*Have you found any treasures at a car boot or jumble sale? Tell us about it. E-mail:helen.mead@nqyne.co.uk