Mining in Cornwall and Devon tin was found as alluvial deposits of cassiterite in the gravels of stream beds. Eventually tin was mined underground; underground mines sprang up as early as the 16th century. Tin lodes were also found in outcroppings of cliffs. Tin is one of the earliest metals to have been exploited in Britain. Chalcolithic metal workers discovered that by putting a small proportion of tin (5 – 20%) in molten copper, the alloy bronze was produced. The alloy is harder than copper. The oldest production of tin-bronze is in Turkey about 3500 BC, but exploitation of the tin resources in Britain is
Antimicrobial copper-alloy touch surfaces surfaces typically manufactured with standard materials (i.e., plastic, chrome, aluminum) were replaced with copper alloys. These included a copper alloy set of sink tap handles (60% Cu, 40% Zn) and a ward entrance door push plate (70% Cu, 30% Zn). Contamination reductions of 90–100% were observed for "Staphylococcus aureus", "Escherichia coli", "Klebsiella pneumoniae", "Acinetobacter baumanii", "Enterococcus" spp., and "Candida albicans" on the copper alloy surfaces versus the non-copper standard surfaces. A microorganism reduction of 100% was observed on the hot tap copper alloy handle. The high degree of clinical performance suggested that copper alloy surfaces may increase the effectiveness of