In September 1940, Charles Mathews & Son, a London firm of lapidarists (people who cut and polish gemstones), contacted Liverpool (now World) Museum’s director. They had a special request. The letter revealed they had been tasked with carrying out ‘important war work’ and they needed a supply of agate. Could the museum help? The Museum dispatched 17 agate specimens, including 10 from the Derby Collection, to the company in London. The agates in the Derby collection came from the 15th Earl of Derby, Edward Stanley, who left his collection to the museum in 1893. His family had an important connection to the museum as his grandfather, the 13th Earl of Derby, was the man who left his natural history collections to Liverpool in 1851 and as a result Liverpool Museum was founded. It was not until 2004 that a museum curator realised the museum had given these important gemstones towards the war effort. She contacted Charles Mathews & Son who still had the letters sent to Liverpool Museum during the war. It was also discovered that 25 fragments of the museum’s Derby Collection had been kept. These were returned to World Museum in 2005.