An article of precious materials can be combined with other materials such as enamel, pearls and precious stones. Such components must be clearly distinguishable and visible. It is not permissible to fill a product with polymer clay or similar fillings.
An article of precious metals may also be a combination of components made of different metals. Such products are known as multi-metal products. A general principle holds that an article of precious metals may not be combined with other metal if such metal resembles the precious metal in appearance and colour. A metal component can be attached to an article of precious metals if it clearly differs from the precious metal, is visible, and the metal component is marked with the METAL mark.
Metal components on an article of precious metals must be marked. A mark may comprise the word ‘METAL’ or the chemical symbol of the metal in question (for example, Cu, AL) or even the mark ‘STEEL’. If a metal component cannot be marked for technical reasons, a mark denoting it can be appended to the array of marks using the ‘+’ sign; for example, ABC 925 + METAL (a responsibility mark, a fineness mark, and a mark identifying the metal component.)
There must be a clear indication on a product if it is made of several different precious metals. However, precious metal of a higher value can be attached to a product without a separate marking.