section_path: History/Antiquity
section_name: Antiquity
paragraph_text: Antiquity
  
  The discovery of bronze (an alloy of copper with arsenic or tin) enabled people to create metal objects which were harder and more durable than previously possible. Bronze tools, weapons, armor, and building materials such as decorative tiles were harder and more durable than their stone and copper (" Chalcolithic ") predecessors. Initially, bronze was made of copper and arsenic (forming arsenic bronze) by smelting naturally or artificially mixed ores of copper and arsenic. The earliest artifacts so far known come from the Iranian plateau in the fifth millennium BCE. It was only later that tin was used, becoming the major non-copper ingredient of bronze in the late third millennium BCE. Pure tin itself was first isolated in 1800 BCE by Chinese and Japanese metalworkers.
  
  Mercury was known to ancient Chinese and Indians before 2000 BCE, and found in Egyptian tombs dating from 1500 BCE.
  
  The earliest known production of steel, an iron-carbon alloy, is seen in pieces of ironware excavated from an archaeological site in Anatolia (Kaman-Kalehöyük) which are nearly 4,000 years old, dating from 1800 BCE.
  
  From about 500 BCE sword-makers of Toledo, Spain, were making early forms of alloy steel by adding a mineral called wolframite, which contained tungsten and manganese, to iron ore (and carbon). The resulting Toledo steel came to the attention of Rome when used by Hannibal in the Punic Wars. It soon became the basis for the weaponry of Roman legions; such swords were, "stronger in composition than any existing sword and, because… would not break, provided a psychological advantage to the Roman soldier."
  
  In pre-Columbian America, objects made of tumbaga, an alloy of copper and gold, started being produced in Panama and Costa Rica between 300 and 500 CE. Small metal sculptures were common and an extensive range of tumbaga (and gold) ornaments comprised the usual regalia of persons of high status.
  
  At around the same time indigenous Ecuadorians were combining gold with a naturally-occurring platinum alloy containing small amounts of palladium, rhodium, and iridium, to produce miniatures and masks of a white gold-platinum alloy. The metal workers involved heated gold with grains of the platinum alloy until the gold melted. After cooling, the resulting conglomeration was hammered and reheated repeatedly until it became homogenous, equivalent to melting all the metals (attaining the melting points of the platinum group metals concerned was beyond the technology of the day).