Tin mining Dredging for ore off the islands shores has churned up sediment which has buried coral reefs where fish live and harmed the local fishing industry. This is despite a prohibition on mining in waters within four miles of Bangka’s shore. Tin mining Tin mining began early in the Bronze Age, as bronze is a copper-tin alloy. Tin is a relatively rare element in the Earth’s crust, with approximately 2 ppm (parts per million), compared to iron with 50,000 ppm. Tin extraction and use can be dated to the beginnings of the Bronze Age around 3000 BCE, when it was observed
Antimicrobial copper-alloy touch surfaces in rooms with copper touch surfaces were significantly lower than in rooms without copper surfaces. "Staphylococci" were the most predominant microorganism isolated and copper was effective in reducing the "Staphylococci" microbial burden. Further studies regarding the clinical implications of copper's intrinsic ability to reduce microbial burdens in hospitals are being planned. Researchers from the Kitasato University School of Medicine conducted antimicrobial studies of "S. aureus", "E. coli", and "P. aeruginosa" on various Japanese copper alloy coins and on copper alloy plates. The microbes were strains from hospital environments. Copper and its nickel-silver, cupronickel, and brass alloys were found to kill