The object found was a large lead ingot or 'pig' (about half a metre long, weighing 63 kilograms). The 'writing' reported by Mr Jones was a cast Latin inscription confirming that it was Roman and about 2,000 years old... The exploitation of Britain's natural resources was one of the reasons cited by Roman authors for the invasion of Britain by the Emperor Claudius in AD 43... Lead ore or galena contains silver as well as lead, and both were valuable commodities for the Romans. Less than a hundred lead ingots of this type are known from the mines of Roman...