Diameter of the balls 12mm, length of the chalcedony strand about 40cm.
The terms "Calchedon" and "Carchedon" are first used by Pliny the Elder in his Latin Naturalis Historia in the 1st century AD. Which stones have been described here, however, cannot be clearly identified on the basis of the descriptions. Over "intermediate stages" like Calcedon, Calzedon, Chalzedon or Kalcedon the name changed to the today common Chalcedon.