AURUNA® 502 Rose Gold Electrolyte

AURUNA® 502 Rose Gold Electrolyte

Neutral, cadmium-free electrolyte for red layers

AURUNA® 502 is a neutral, cadmium-free gold copper electrolyte working without free cyanide. The red surfaces are bright, very hard and abrasion-resistant.

AURUNA® 502 is mainly used for decorative coatings, but it is suitable for technical applications such as slip rings as well. As gold-saving, low-carat layers, the surface exhibits very good corrosion and tarnish resistance.

The gold copper electrolyte can be used for rack and barrel plating, it can deposit layers of up to max. 10 μm in thickness.

Electrolyte characteristics

Electrolyte type


Metal content

4 (3.5 - 4.5) g/l Au 3 (2.5 - 3.5) g/l Cu

pH value

7.5 (7.2 - 8.0)

Operating temperature

57 (55 - 60) °C

Current density range

0.5 (0.3 - 0.8) A/dm²

Plating speed

Approx. 0.15 μm/min at 0.5 A/dm²

Anode material

Pt-Ti (type PLATINODE® Pt/Ti)

Coating characteristics



Alloy composition

75 wt.% Au 25 wt.% Cu

Colour of deposit





380 - 400 HV

Max. coating thickness

Approx. 10 μm

Density of the coating

Approx. 15 g/cm³


  • Gold-saving coatings (approx. 18 ct)
  • Cadmium-free
  • Red gold-copper layers
  • Resistant to tarnishing and corrosion
  • Maximum layer thickness approx. 10 μm
  • High hardness (380 - 400 HV), abrasion-resistant
  • Suitable for rack and barrel


  • Accessories
  • Jewellery
  • Watches
  • Bathroom fittings
  • Lighting
  • Spectacle frames
  • Writing implements
  • Slip rings


  • Produktblatt-auruna-502-en-screen-20190416.pdf

Your contact person

Markus Legeler

Manager Sales International
T: +49 7171 607 204
F: +49 7171 607 316

Find a representative in your region


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