AURUNA® 503 Rose Gold Electrolyte

AURUNA® 503 Rose Gold Electrolyte

Neutral, cadmium-free electrolyte for red layers

AURUNA® 503 is a neutral, cadmium-free gold-copper electrolyte for the deposition of bright red surfaces. It works without free cyanide.

AURUNA® 503 is especially suited to decorative but also technical applications, such as sliprings. Special features of this electrolyte are its long lifetime and fast deposition speed. For low-carat gold-saving layers, it also offers good resistance to corrosion and abrasion.

The gold-copper electrolyte can be used for rack and barrel plating and can achieve layers up to 5 μm in thickness.

Electrolyte characteristics

Electrolyte type


Metal content

6 (5 - 7) g/l Au 2.5 (2.0 - 3.0) g/l Cu

pH value

7.5 (7.3 - 7.8)

Operating temperature

65 (60 - 70) °C

Current density range

0.8 (0.6 - 1.2) A/dm²

Deposition rate

approx. 0.25 μm/min at 0.8 A/dm²

Anode material

Pt-Ti (type PLATINODE® Pt/Ti)

Coating characteristics


Gold Copper


75 wt.% Au 25 wt.% Cu

Colour of deposit

rose gold



Hardness of deposit

380 - 400 HV

Max. coating thickness

approx. 5 μm

Density of the coating

approx. 15 g/cm³


  • Gold-saving coating (approx. 18ct)
  • Long lifetime
  • Fast deposition speed
  • Cadmium-free
  • Red gold-copper coatings
  • Resistant to tarnishing and corrosion
  • Maximum layer thickness approx. 5 μm
  • Very hard (380 - 400 HV), abrasion-resistant
  • Suitable for rack and barrel


  • Accessories
  • Jewelry
  • Watches
  • Bathroom fittings
  • Lighting
  • Spectacle frames
  • Writing utensils
  • Sliprings


  • Produktblatt-auruna-503-en.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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