Glossary - Coining a Term

The world of coins can sometimes be confusing. We’d like to make things simpler!

99999:  Describes gold of extremely high purity (only 10 parts per million impurity).

9999:  Describes 24-karat gold of high purity (only 100 parts per million impurity). Used to designate Gold Maple Leaf bullion coins.

Annealing:  Process of heating and cooling metal strips in a low-oxygen furnace in order to relieve stresses.

Antique:  A chemical toning process used for medallions which prematurely tarnishes the coin to simulate the natural darkening that occurs as metal oxidizes 

with age.

Assay:  To test the weight and metal purity of a coin, wafer or bar.

Blank:  The blank metal disk that is eventually struck and turned into a coin.

Brilliant uncirculated:  A brilliant relief is struck on a brilliant field. Brilliant uncirculated coins are struck up to two times on numismatic presses.

Bullion:  Bars, ingots, plates, wafers and coins made from precious metals, usually gold or silver.

Coining:  Process by which the image is struck onto blanks using a die engraved with a mirror image of the design.

Degreasing:  Process by which any remaining oil residue is removed from blanks after they are washed and before they are minted.

Design:  The artist’s rendering on the reverse side of a coin, along with any words, nominal values, decorative elements, colouring, hologram effect, etc.

Die:  A tool that strikes an image or relief on a blank, turning it into a coin.

Effigy:  A portrait found on the obverse side of a coin. Canadian coins bear effigies of the reigning monarch, Canada’s official head of state.

Engraving:  An artist’s design that has been adapted and transferred to a medium that will ensure the best relief for minting.

Field:  The flat part of the coin (the background) on which the relief is struck.

Finish:  The appearance or surface texture of the coin’s relief.

Minting:  The process of manufacturing coins.

Obverse:  The ‘heads’ or face side of a coin.

Proof:  Coins with a frosted relief over a brilliant field. Proof coins possess the highest-quality finish for a numismatic coin, and are usually struck twice to reveal

the smallest details of the coin’s design.

Reeding:  Grooved or serrated lines found around the edge of some coins.

Relief:  The relief is the raised or three-dimensional image found on a coin’s field.

Reverse:  The opposite of obverse – the ‘tails’ side of a coin.

Reverse proof:  High-quality proof finish in reverse: brilliant, reflective details on a frosted or slightly matte field. These coins are individually passed through the

presses. Multiple strikes are applied to achieve maximum detail and finish.

Rim:  The raised portion that runs around the perimeter of a coin.

Rolling:  Gold, silver and other metals for coinage start out as cast bars. They are rolled into strips, each specific to the size and thickness of the minted coin.

Specimen:  A brilliant image relief is struck against a matte or lined background in order to achieve maximum visual impact. Specimen coins are struck up to two

times on numismatic presses.

Uncirculated:  Either a circulation coin that has never been circulated or a coin with a brilliant field over a brilliant relief.

Washing:  Process by which rimmed blanks are tumble-washed in a drum and dried by hand.