What is a Proof Coin?
Bullion dealers often list a variety of gold and silver coins as being of varying conditions. Below we explain the different names for the striking standards used, and the coin finish for each standard.
Coin making is a complex process, but the production cycle is quite straightforward: blanks (metal coin discs) are cut out from metal sheets. These blanks are then washed and dried ready for production. Refiners like The Royal Mint will select the best blanks to become proof coins, then the next best as Brilliant Uncirculated, and the remainder become Bullion coins.
A proof coin is the highest quality of coin a mint produces. These coins are attributed a
much higher value than the metal itself due to their status as a commemorative coin.
Proof coins are struck using hand-finished dies. This means an expert will etch into the
metal die to produce a mirror image imprint, ready for a machine to stamp a blank coin
disc. The decision to hand-finish the dies means that there will be no imperfections
before a coin is produced.
The process for production sees a high-quality proof blank placed into a coin press. This
is done by hand. The coin is then struck six times, at the lowest speed and lowest pressure
of the three coin types. This avoids any blemishes, but for additional peace of mind the
operator will also clean the dies before and after usage with air, cleaning off any dust or
This meticulous process means that it takes an hour to strike 50 proof coins – a stark
contrast with the 3,000 per hour rate for bullion silver coins – and the coin design dies
are sharpened and polished after every few hundred strikes.
Producers such as The Royal Mint will only issue a small mintage of proof coins of each
type per year, and these come in a special gift box with a certificate of authenticity.
The next highest quality coins are the Brilliant Uncirculated coins. These often feature
the abbreviations BU, B.U, or B.UNC in product names.
As you can see from the image to the right, the finish is excellent for these coins, but
lacks the mirror-like sheen of the proof coins.
This quality is similarly achieved by a hand-finish for the dies used to imprint upon the
coin, but unlike proof coins the Brilliant Uncirculated coins are machine-fed for their
production. BU coins are struck twice in the minting process, making them twice as
quick to produce compared to proof coins for only marginally less quality.
Brilliant Uncirculated coins can be boxed and certificated, like proof coins, but they
can also be capsuled like bullion coins.
Arguably the worst of the three coins, Bullion Coins may seem to be just a poor man’s
collectable, but this is an unfair criticism. Bullion coins are mass produced weights
designed to retain wealth, and at BullionByPost we primarily sell bullion coins in the
form of Sovereigns, Britannias, Krugerrands, and other major coins.
Bullion coins have a very good finish, though admittedly not as crisp a contrast as the
Brilliant Uncirculated coins or the sheen finish of the Proof Coins. Bullion coins ARE
uncirculated however, and at BullionByPost we get British bullion coins direct from
The Royal Mint to ensure the highest quality for our customers.
The Royal Mint produces bullion coins with a single strike, machine feeding the coins
ready to be stamped. Their factory in Llantrisant, South Wales, can produce 250 gold
bullion coins and 3,000 silver coins per hour.
Bullion coins may not be as exquisite as the Proof or Brilliant Uncirculated products,
but they are the most cost-effective option, and share almost all the same design work.
Bullion coins can either come in individual protective plastic capsules or in tubes of
10 or 25 if ordering large quantities.
Which is the best coin?
The reality is that there is limited difference between the three coin types. The designs are nigh on identical, aside a little extra work for the finish on each the Proof and Brilliant Uncirculated coins. If money is no issue then the Proof Coin would be the logical option, but some collectors prefer the crisp design of a B.U coin rather than the mirrored proofs.
One word of caution for collectors is that you cannot guarantee the value will be matched on re-sale of your collectable coins. Bullion coins are a lot easier to predict in terms of pricing, with their value being based on the metal market prices.