A man has launched a social media appeal to try to track down the owner of a jewelled ring he found on a train.
Darren Francis, 45, went for drinks with a friend in Guildford on Friday evening, before getting on the 22:55 BST service to Waterloo back home.
He spotted the ring "glistening" on the floor just before he got off at Wimbledon.
Mr Francis's Twitter appeal, posted on Friday, has so far attracted hundreds of retweets.
"I was just about to get off at Wimbledon and then I saw it glistening on the floor," he said.
"It was obviously a ring with a big stone in it."
Going the extra mile
Mr Francis thinks that because his carriage was almost empty, the ring may have been dropped by somebody travelling to Guildford on an earlier service.
He will hand the ring into staff at Waterloo station on Tuesday, when the lost property office is next open.
"I've never been in a situation where I have handled a ring that's like this," he said.
"It feels heavy-ish, but that's the extent of my knowledge of precious rings."
After urging Twitter users to help him track down the owner, he asked jewellers to value the ring.
They told him it was most likely made of fake jewels so would not be very valuable - but that if a diamond that size had been real it could have been worth about £10,000.
"Even if it's not real, I'm sure it could still hold huge sentimental value for someone, so I really hope we can find them."
South Western Railway, which runs the lost property office at Waterloo, said items they can keep are stored securely for three months.
A spokesman thanked Mr Francis for "going the extra mile" by posting on social media before handing in the ring.
Items that have recently been stored at their lost property office include a barrister's wig, a leather chair and a pair of false teeth.