A "lost" vein of rare Blue John stone has been rediscovered in a Peak District cavern, solving a 68-year-old mining mystery.
In 1945 a miner by the name of John Royse reported finding an amazing deposit of the renowned stone in Treak Cliff Cavern, Castleton.
He told 19-year-old Peter Harrison, whose family had taken over the running of the Derbyshire mine, but sadly Mr Royse was taken ill and died before he could reveal the exact location.
For almost seven decades, Mr Harrison and his family have toiled away in the mine in search of the lost vein, but only found other lesser deposits.
The new find, which should keep the mine busy for the next decade at least, was uncovered deep in the ground beneath an old piece of carpet.
Mr Harrison said: "I was just a young lad of 19 when my family took over the running of Treak Cliff Cavern back in 1945.
"The old miner, John Royse, was not in the best of health and was retiring.
"He told me of this fantastic deposit of Blue John he had found and asked me to help him get it out. We planned to return to the cavern the next day but sadly John Royse was taken ill and died. Over the years I have spent countless hours searching for that deposit."
The honour of discovering the "lost" stone fell to Mr Harrison's grandson, John Turner.
The 21-year-old said: "I am learning the art of Blue John mining from Gary Ridley, the mine manager, who has been mining here for over 15 years.
"Gary has been teaching me what to look for and the tell-tale crystal structures in the rock that could mean a vein of Blue John lies beneath.
"It was while we were stood talking at the bottom of the ladder that leads to the upper galleries that I noticed something unusual on the floor.
"After an hour of digging through muddy deposits, I was amazed to come across an old piece of carpet supported by some wooden batons.
"I couldn't believe my eyes when we pulled away the old carpet and there was this most amazing deposit of Blue John stone. It was right under the ladder that my grandfather put in decades ago. He must have walked over John Royse's old find thousands of times over the years."
Mr Harrison added: "When my grandson phoned to tell me he had found John Royse's old deposit, I couldn't believe it.
"After all these years it was right under my feet! I'm 87 now and retired years ago, but when I heard the news I just had to put on my old mining overalls and make the trip back into the cavern to see the deposit for myself."
Vicky Turner, Peter's daughter and John's mother, who now manages Treak Cliff Cavern, said: "I grew up with stories of John Royse's lost deposit.
"To be honest, I thought it might have been a bit of an old miner's tale. If my father hadn't found it after all these years, maybe it didn't exist. It is a fantastic discovery. John is learning the trade and has a great eye for it, it must be in his blood.
"We have started removing some of the Blue John to test for its quality and it is some of the best most beautifully veined Blue John ever to come out of Treak Cliff.
"It is a sizeable deposit and we conservatively estimate that there is enough Blue John stone in this deposit to keep us busy for the next decade at least."