All New Zealand Mint collectible coins are Proof coins. A Proof is the absolute highest quality coin a mint can produce; they have no equal in sharpness or brilliance. These specialty made coins are so finely sculptured that extreme details are noticeable. They are undoubtedly the best choice if you want to own or gift a coin with the highest levels of craftsmanship and design detail.
Proof coins are produced when two dies strike a blank piece of metal. One die is engraved with the front (obverse) design for the coin. The other die has the back (reverse) coin design on it. The dies are all hand-finished. This is to ensure that all imperfections are removed before they're used to strike a coin. The blanks will be struck up to six times, at a lower speed and with less pressure than other finishes. By striking it more than once the metal is forced into all the crevices of the die, thereby giving the coin a smoother, sharper finish and fine detail to the images.
The Proof dies are regularly re-worked and re-polished to maintain a blemish-free finish and thereby ensure that no marks or imperfections are caused during striking. After striking, each coin is removed from the press and checked for imperfections. As a result of the extra care and attention, each die may only strike a few hundred coins before it has to be re-polished.
Interestingly, not all Proof coins have the same finish. The most common example is where the background of the design - the ‘table’ or ‘field’ - has a highly-polished mirror-like finish (in fact when you stand back and look at a proof, you’ll see your reflection on its surface) and a frosted effect is applied to the raised foreground - the ‘relief’. This gives a higher contrast and more definition to the coin design. This contrasting finish is often called ‘cameo’. The frosted effect is achieved by sand and glass bead blasting the surface of the die, with the table protected. On rare occasions the coin will be finished with ‘reverse frosting’, where the table is frosted and the relief polished. There are also variations of frosting, such as Matt and Satin. Proof coins have, on a few occasions, also been given an all frosted finish.
It's not the quality of the finish alone that makes Proof coins so appealing to collectors. Each coin is approved by the country that issues it and that country’s effigy appears on the obverse of the coin (this is quite often the Queen's head or the country's Coat of Arms). This makes the coin legal tender in that country.
The government of that country also agree the amount of coins that can be produced. This is called the mintage. The coins in the mintage therefore become limited-edition coins, as legally no more of the same coin can be produced. Proof coins are also often struck with low mintages, which makes them rarer than other commemorative coins.
A Proof coin's exceptional detail combined with its aesthetic appeal make them extremely popular. They usually feature beautiful and thoughtful designs. And they often display stunning images of people, characters, places, and animals etc. that are dear to people's hearts; they are intended to be cherished.
Proof coins are made for collectors or special occasions; they are not coins intended for general circulation. Because they're designed to be uncirculated, these coins shouldn't show signs of wear. That means there will be no handling marks and few, if any, nicks or other abrasions - like you always see on every day pocket change!
New Zealand Mint's collectible coins come in unique, themed outer packaging that enhances the coin experience. Every coin has a Certificate of Authenticity. This confirms the specifications of the coin and its number in the mintage.
The coins themselves are carefully packaged to showcase and preserve their exceptional finish. They are contained within special holders for protection and to help maintain their condition. Every one undergoes special care and is never touched by bare, human hands.