A pair of “gold plated circular rimmed spectacles” worn by Mahatma Gandhi in South Africa are to be auctioned in Britain at an estimated price range of £10,00015,000, but are expected to fetch much more.

Auctioneer Andrew Stowe from East Bristol Auctions in Hanham, Bristol, said the spectacles, which have been entered into an online auction of “military & history” memorabilia on August 21, were “probably the most important find we have ever had as a company”.

He said the owner “nearly had a heart attack” when told their value.

Stowe said: “We came in one morning, and there, poking rather precariously out of our letter box, was a small plain white envelope. In the envelope was the pair of spectacles, along with a note that read, ‘These were Gandhi’s glasses,’ and a phone number for the owner.

“Someone popped them into our letterbox on a Friday night and they stayed there until Monday — literally hanging out. They were just in. They could quite easily have been stolen or fallen out or just ended up in the bin.

“One of my staff handed them to me and said there was a note saying they were Gandhi’s glasses. I thought, ‘That’s an interesting one’ and carried on with my day.”

He “almost fell off his chair” when he realised the significance of the spectacles.

Stowe continued: “It was the most bizarre five minutes of my career. A telephone call later and we learned the full story and set about our research. Once we dug a little deeper, we realised these glasses were of huge historical importance. We looked into the dates and they all match up, even the date Gandhi started wearing glasses.”

“Gandhi is an iconic figure in world history. When one thinks of him, you conjure up the image of his shawl, his sandals and, of course, his glasses.”

The catalogue has a note on the spectacles and the man who had worn them: “Mahatma Gandhi (18691948) – A pair of early 20th century c1920 gold plated circular rimmed spectacles by repute owned and worn by Mahatma Gandhi. The spectacles of usual form, with sprung gold plated arms and prescription lenses. Jointed by a gold plated nose bar. The spectacles formed an important and somewhat iconic part of Gandhi’s overall appearance. It was known that he would often give away his old or unwanted pairs to those in need or those who had helped him. A rare and important pair of spectacles.

“Provenance; given to the vendor’s Uncle c19201930 by Gandhi whilst in South Africa. The uncle working for British Petroleum at the time and was stationed in South Africa, and it can be presumed that these were gifted by way of thanks from Gandhi for some good deed. A note from the vendor is included.”

Objects related to Gandhi have fetched a lot of money at auctions in the past, with a small shawl worn by him selling for £40,000 in 2013. A pair of wellworn sandals sold in the same year for £13,000.

Gandhi will be the first ethnic minority figure to feature in a British coin brought out by the Royal Mint.