Occasionally you see these news pieces telling of rare, misprinted coins that are in circulation and worth a fortune if you happen to have one. This is one of those pieces.

Apropos of nothing, we looked into the most valuable coins still in circulation in Australia and read about The Wavy 20 – which sounds like a great surf-pop big band, but is actually the collectors’ term for a series of 1966-printed 20c coins.

The way to figure out if you have such a coin in your pockets is to look at the bass of the ‘2’ on the tail side of the coin.

The majority of the 58.2 million 20 cent pieces pumped into circulation during 1966 — the year decimal currency was introduced in Australia — have a straight base on the ‘2’, while a select few have a wavy bass – hence the natty name.

Here’s a photo, courtesy of Sterling Currency.

20c wavy 20

It’s subtle, but notable. Experts disagree as to whether this is a result of errors formed during the pressing of the coin, or simply a separate, quickly-discontinued design.

This eBay auction is selling one for $800, and individual coins have fetched thousands. Time to get into the habit of checking your 20c pieces before chucking them into that gumball machine at the takeaway near your house, it would seem.

20c

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