[lexlash]

At least they gave sizes in American and metric this time.

Snark aside, rounds to 30mm diameter and 6.5-8.5mm height, if memory serves.

[huppeldepup]

  EU 10-euro collector coin

Greek edition: 40 mm or 28.25 mm diameter depending on coinage year. The German ones are 32.5 mm. The Irish are 38.61 mm. Etc.

[DemocracyFTW2]

so, a perfect object to base a precise measurement on, with "a pinch of salt"