A pensioner who was about to bin a ring she'd bought at a car boot sale must be incredibly glad that she didn't, as it turns out that it's worth about £2 million.
Yes, two million quid, for something that she presumably picked up in a school car park.
Not a bad find, all things considered.
It was purchased many years ago by a woman - who wishes to remain anonymous - in her 70s, who just assumed that the ring would have no particular value to it.
As she now knows, that was completely wrong.
Eventually, a neighbour convinced her to get the stone valued, and she was eventually told that the true value of the ring was 'off the scale'.
Mark Lane, from Featonby's Auctioneers in North Shields, told BBC News that the woman simply wandered in off the streets with the ring, asking if he'd mind appraising it.
He explained: "She just thought she would bring it in as she was passing."
Lane continued: "It had been in a box along with her wedding band and a number of low-value costume jewellery items.
"We saw quite a large stone, bigger than a pound coin, and I thought it was a CZ [cubic zirconia, a synthetic diamond lookalike]."
It was most certainly not.
He added: "It sat on my desk for two or three days until I used a diamond tester machine. We then sent it off to our partners in London before it was certified by experts in Antwerp, Belgium, who confirmed it is 34 carat."
The diamond itself is absolutely massive.
In fact, it's about the same size as a pound coin, and Mr Lane said it's the biggest one that he's seen in the five years he's been the proprietor of the auctioneers.
The woman obviously doesn't want anyone to know who she is, but we do know that she loved going out to car boot sales and attempting to bag herself a bargain.
It's fair to say she's managed that here.
Lane said: "She told us she'd been having a clear-out and that it nearly went in the bin before her neighbour suggested bringing her items to us to get valued.
"The colour, the clarity, the size... to find a 34-carat diamond is off the scale."
Now, the diamond is set to go under the hammer on November 30, and it is being stored in a very secure place in London's Hatton Gardens until then.
Featured Image Credit: North News