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
Billon (alloy) Billon (alloy) Billon is an alloy of a precious metal (most commonly silver, but also mercury) with a majority base metal content (such as copper). It is used chiefly for making coins, medals, and token coins. The word comes from the French "bille", which means "log". The use of billon coins dates from ancient Greece and continued through the Middle Ages. During the sixth and fifth centuries BC, some cities on Lesbos used coins made of 60% copper and 40% silver. In both ancient times and the Middle Ages, leaner mixtures were adopted, with less than 2% silver content. Billon