The museum has a specimen of international importance, the Charnia fossil. This was the first fossil ever described from undoubted Precambrian rocks. Until then, no large (non-microscopic) forms of life were known to exist at that time. The object in the museum – "Leicester's fossil celebrity" – is a holotype. It is the actual physical example from which the species was first identified and formally described. "Charnia masoni" was named after Roger Mason. He discovered it in Charnwood Forest in 1957, when he was a schoolboy. He who went on to a career as an academic geologist. The fossil had been discovered a year earlier by a schoolgirl, Tina Negus, "but no one took her seriously".