Researchers have opened a 400-year-old Elizabethan padlock for the first time after using X-ray imaging to crack its four-letter combination, Live Science reported. The brass lock was part of the Ann Francis treasure hoard, named after a British merchant ship that wrecked in a storm off the coast of Wales in 1583. Researchers believe the lock once secured a chest aboard the ship before becoming separated from whatever it protected. The combination, once the team could see inside the mechanism, was "ANCE."
Some of the Ann Francis's cargo was recovered at the time of the wreck; the rest was claimed by the sea. In recent decades, dredging and storms on Margam beach in South Wales have exposed more of the lost treasure. Between 1996 and 2017, metal detectorist Peter Hughes found the lock and much of the hoard, including gold and silver coins. Amgueddfa Cymru, or National Museum Wales, later acquired the lock and worked with researchers at Cardiff University to decipher it. The team used micro-CT scans, which make thousands of X-rays that can be assembled into a 3-D digital image. By matching internal notches to external letters, they read the code without forcing the dials. "We normally use this technology to study bones and other biological structures, so investigating a 400-year-old padlock was certainly a first for us," David Williams, a research associate at the Musculoskeletal Biomechanics Research Facility at Cardiff University, said in a statement.
The Ann Francis was owned by Francis Shaxton, a merchant and notorious smuggler. He claimed the ship was sailing along the eastern English coast from King's Lynn to Hartlepool, when it was actually heading to Spain to deliver a cargo of wheat. Spain paid for grain in gold and silver from colonial conquests in the Americas, according to the museum. On the evening of Dec. 28, 1583, traveling back from Spain, the ship was caught in a violent storm and wrecked off Margam beach. A parish register noted the loss of 14 sailors that month, which could have been the ship's crew; the deaths were blamed on a supposed witch. Locals looted the wreck before a legal dispute broke out over who had the right to its goods. One Welsh lord inventoried items he impounded, including cannons, guns, a piece of mast, Spanish silver, and three chests with their locks broken. The newly cracked lock could have secured one of those chests.
Hughes later found the lock near a previously undiscovered stash of Spanish silver coins and coin weights. He said the ring dials still turned after more than 400 years under the sand, but he could never find the right combination. Museum staff, hearing grit inside the dials and facing more than 1,000 possible combinations, did not want to damage it. The scans gave them a nondestructive answer. The verified result is the code and the lock's link to a dated wreck. What the chest once held, and why the letters spell "ANCE," remains unanswered.