Bronze Age metallurgy: 2mm disc with 99.5% gold. The bronze plate was forged through repeated cycles of heating until thin and even, then precisely inlaid with gold foil The disc measures 12 inches (30 cm) in diameter and weighs 5 pounds (2.5 kg) Thickness is only 2 millimeters
This 12-inch Bronze Age disc is only 2mm thick yet weighs 5 lbs — forged through ~10 heating cycles. Gold foil under 0.1mm thick was pressed into recesses just thousandths of an inch deep. Material sources traced to Austria, Cornwall, and possibly the Balkans 🌟🔍
Key Facts
- The bronze plate was forged through repeated cycles of heating until thin and even, then precisely inlaid with gold foil
- The disc measures 12 inches (30 cm) in diameter and weighs 5 pounds (2.5 kg)
- Thickness is only 2 millimeters
- Gold pieces were pressed into shallow recesses only a few thousandths of an inch deep
- Gold foil was less than 0.1 millimeter thick
- Gold purity is about 99.5%, an unusually refined standard for that era
- Production required around 55 heating cycles to nearly 700°C (1300°F)
- Copper was traced to mines in the Austrian Alps
- Gold was sourced from Cornwall, England
- Tin possibly from the Balkans or Iberia
- Materials came from regions over a thousand kilometers apart
Related site: Nebra sky disk — view location, images, and history on the Ancient Nerds map.
Source: 3,600-Year-Old Star Map Found in Germany: Nebra Sky Disc by Universe Inside You