Tin mining to trace metal content in the copper ore It was soon discovered that the addition of tin or arsenic to copper increased its hardness and made casting much easier, which revolutionized metal working techniques and brought humanity from the Copper Age or Chalcolithic to the Bronze Age around 3000 BC. Early tin exploitation appears to have been centered on placer deposits of cassiterite. The first evidence of tin use for making bronze appears in the Near East and the Balkans around 3000 BC. It is still unclear where the earliest tin was mined, as tin deposits are very rare and
Tin-silver-copper Tin-silver-copper Tin-silver-copper (SnAgCu, also known as SAC), is a lead-free (Pb-free) alloy commonly used for electronic solder. The tin-silver-copper alloy has been the prevailing alloy system used to replace tin-lead because it is near eutectic, with adequate thermal fatigue properties, strength, and wettability. Lead-free solder is gaining much attention as the environmental effects of lead in industrial products is recognized, and as a result of Europe’s RoHS legislation to remove lead and other hazardous materials from electronics. Japanese electronics companies have also looked at Pb-free solder for its industrial advantages. Typical alloys are 3–4% silver, 0.5–0.7% copper, and the balance