Barry S. writes: Ancient Greek coins are round. Modern US coins are round. Casino chips seem to be round as well. Why are coins round, instead of square or rectangle? Thank you, Barry.
So you can roll them down the bar…… Actually, the first coins were rectangular bars of electrum (an alloy of gold and silver) punched with an round official symbol but accountants found round coins easier to stack and count. Also, round coins are easier to Mint. A circular die simply needs to line up with the opposing circular blank to mint a coin successfully.