The new 12-sided pound coin, the shape of which resembles the old three-penny bit, entered circulation in March and boasts new high-tech security features The old round pound is on the way out ...

The 12 sided £1 coin replaced the old round design in 2017(Getty) Check Your Change clarifies that the coins with this mark were sold as part of a pair set from the Royal Mint in 2016.

The coin in question is a £1 coin from 2016. This will be a newer-style £1 with 12-sides. Although the 12-sided coins were officially introduced in March 2017, the Royal Mint produced more than ...