A team from Cardiff University has successfully unlocked a 400-year-old brass padlock recovered from a shipwreck off the coast of Wales, using micro-CT scanning technology to decipher its four-letter code. The lock, believed to have been submerged since 1583, was found near Margam Beach.
For centuries, the padlock remained sealed after the ship, identified as the Ann Francis, was wrecked during a storm on December 28, 1583, while en route from Spain to King's Lynn. The vessel was blown off course and ran aground.
The lock was discovered by metal detectorists, and its remarkable condition allowed the dials to turn easily after centuries underwater. Scientists collaborated with museum specialists to analyze the artifact without causing any damage. Using high-resolution micro-CT scans, they created a detailed 3D model of the lock's internal mechanism. This allowed them to see how the internal notches aligned with the rotating lettered dials.
The team identified the correct four-letter combination as "ANCE." This allowed them to open the lock, revealing it to be the first time in over 440 years it had been opened. Experts suspect the lock may have secured a small chest containing valuable possessions, possibly silver coins or other valuables, although the chest itself has not been found.
Alastair Willis, senior curator of coins and Welsh economic history at Museum Wales, noted that while Elizabethan combination locks exist, this particular one is exceptionally well-preserved and linked to a dated wreck, making it a unique find. The padlock is now on display at the National Waterfront Museum in Swansea alongside other artifacts from the Ann Francis hoard, which include approximately 870 gold and silver coins, personal belongings, and various utensils dating from the late 15th to 16th centuries.