Depending on the subject and the style of the medal, touches of colour may be used to create some fantasy in the artwork.
Some designs including logos or blazons will require the use of colour. Other artworks are designed with colours as an essential component.
Liquid Resin Colours
Most of the time, colours are made of liquid resins which are applied with a needle in small areas divided by metal borders. Colours can be used on any flat area of a medal but not on 3D areas.
The resin becomes solid when it is cooked at a temperature of 85°C (185°F).
Once the colours are dry, they can be emery-grinded so that the surface of the coloured areas becomes perfectly flat. If they are not emery-grinded, their surface will show a slight cup effect.
Hard Enamel Colours
In some cases, medals are coloured with real hard enamel colours made of silicon and metal oxide: the colours are vitrified at 850°C (1562°F) and permanently solidified.
They are then scoured after being enamelled and polished.
Given the fact that real hard enamel colours are extremely resistant, this colouring process is often used for car emblems or creations that require outdoor conditions endurance.