Crosby Garrett Helmet some point the helmet was repaired using a bronze sheet which was riveted across two splits. Only two other Roman helmets complete with visors have been found in Britain – the Newstead Helmet and Ribchester Helmet. The helmet and visor were cast from an alloy consisting of an average of 82% copper, 10% zinc and 8% tin. This alloy was probably derived from melted-down scrap brass with a low zinc content, with which some tin had been added to improve the quality of the casting. Some of the fragments show traces of a white metal coating, indicating that the visor
Sundown Tin and Copper Mine and were mined from different shafts. With rising prices the mine was operating again in 1897, and much development work was carried out in 1898. By 1899 a smelter must have been erected, as 470 tons of ore was smelted for 53 tons of matte containing 30% copper and 50oz silver per ton, and 20 men were employed. More ore was raised in 1900, but the mine was under exemption through 1901-1903, a time of low copper prices. In 1904 the mine was described as having an open-cut on the tin portion, and on the copper section a tramway ran