1 Crown - Elizabeth II Chang Heng - Seismograph, Silver Proof

The Chang Heng commemorative belongs to the Isle of Man's prolific 1990s series celebrating scientific achievement — a program that leaned heavily on subjects with no particular connection to the island. Chang Heng, the Han dynasty polymath active in the first and second centuries AD, built his seismoscope around 132 AD, nearly two millennia before the instrument's principles were formally rediscovered in the West. His device reportedly detected a earthquake several hundred miles away while court officials in Luoyang felt nothing.

Struck by Pobjoy Mint under license from the Manx government.