While in the past mostly glass ware and ceramics (table china) were coated for decorative purposes with gold or platinum, precious metals have since quite a few years been applied to non-metallic substrates such as ceramics, glass, or plastics to make their surfaces electrically conductive. To coat these surfaces fine powders of the precious metal are dispersed in a carrier containing a paint basis and organic solvents. Such preparations can be applied by screen or tampon printing, by spraying, immersion, or with a paint brush.

The firing preparations in liquid or paste form are widely used in electrical and electronic engineering and especially in the thick-film technology ''(Table 8.2)''. The precious metal filler material is mostly pure silver because of its high electrical conductivity. During firing in an oxidizing atmosphere at temperatures between 400 and 850°C a well adhering and highly conductive surface layer is formed.

When utilizing screen printing techniques any shapes of conductive patterns can be created ''(Fig. 8.2)'' resulting in conductive paths with good electrical properties and high temperature stability.