All precious metals can be electroplated with silver and gold by far the most widely used ones <xr id="tab:Precious Metal Electrolytes for Technical Applications"/> <!--(Tab. 7.2) --> and <xr id="tab:Precious Metal Electrolytes for Decorative Applications"/> <!--(Tab. 7.3)-->.

<caption>'''<!--Table 7.2: -->Precious Metal Electrolytes for Technical Applications'''</caption>

=====<!--7.1.1.1.2 -->Non-Precious Metal Electrolytes=====

The most important non-precious metals that are deposited by electroplating are: Copper, nickel, tin, and zinc and their alloys. The deposition is performed in the form of pure metals with different electrolytes used <xr id="tab:Typical Electrolytes for the Deposition of Non-Precious Metals"/><!--(Table 7.4)-->.

<caption>'''<!--Table 7.3: -->Precious Metal Electrolytes for Decorative Applications'''</caption>

<caption>'''<!--Table 7.4: -->Typical Electrolytes for the Deposition of Non-Precious Metals'''</caption>

Since precious metals are rather expensive it is necessary to perform the electroplating most economically and coat only those areas that need the layersfor functional purposes. This leads from overall plating to selective electroplating of strip material in continuous reel-to-reel processes. Dependingon the final parts design and the end application the processes can be applied to solid strip material as well as pre-stamped and formed continuous strips or utilizing wire-formed or machined pins which have been arranged as bandoliers attached to conductive metal strips.

The core part of selective precious metal electroplating is the actual electroplating cell. In it the anode is arranged closely to the cathodic polarizedmaterial strip. Cathode screens or masks may be applied between the two to focus the electrical field onto closely defined spots on the cathode strip.

For a closely targeted electroplating of limited precious metal coating of contact springs so-called brush-electroplating cells are employed <xr id="fig:Brush Tampon plating cell"/> <!--(Fig. 7.1)-->. The “brush” or “tampon” consists of a roof shaped titanium metal part covered with a special felt-like material. The metal body has holes in defined spots through which the electrolyte reaches the felt. In the same spots is also the anode consisting of a fine platinum net. The pre-stamped and in the contact area pre-formed contact spring part is guided under a defined pressure over the electrolyte soaked felt material and gets wetted with the electrolyte. This allows the metal electroplating in highly selective spots.