20 pence

What is BU?

BU is an abbreviation explicitly not allowed on Numista, but still appears thousands of times. It stands for “brilliant uncirculated”.

Thank you 

Coins issued by the Royal Mint come in three broad categories:

Circulation: Exactly what it sounds like, coins issued for general use in circulation

Brilliant Uncirculated “BU”: These are coins usually struck to similar standards as circulation but are put into collector packs.

Proof: These coins are struck differently (usually things like repeatedly struck at higher pressure) which results in the detail being finer. Again, for collector packs but at a higher price point.

If I recall correctly, 1982 was the first year that both BU and proof sets appeared; earlier years were proof only.

Some photos of the BU set.

And the proof set.