RHODUNA® 471 Black Rhodium Electrolyte

RHODUNA® 471 Black Rhodium Electrolyte

Abrasion-resistant and crack-free dark layers

RHODUNA® 471 Black gives jewelry a high-end anthracite to black finish. The level of darkness can be adjusted. The electrolyte is easy to use and the deposits are sure to impress with good color consistency and brightness retention. Thanks to its good corrosion resistance, the electrolyte is ideal for applications where black ruthenium cannot meet abrasion requirements.

The electrolyte produces crack-free surfaces even in thicker layers. On a substrate, it is advisable to pre-coat with either gold or rhodium.

To achieve very dark results and perfect abrasion resistance, it is necessary to post-treat the coated parts with RHODUNA® 471 Black.

Electrolyte characteristics

Electrolyte type


Metal content

2 (1.8 - 2.2) g/l Rh

pH value

1.7 (1.0 - 2.0)

Operating temperature

60 (55 - 65) °C

Current density range

0.5 (0.25 - 2) A/dm²

Plating speed

0.04 μm/min at 1,0 A/dm²

Anode material

Pt-Ti (type PLATINODE® Pt/Ti)

Coating characteristics



Colour of deposit

Grey to anthracit (black)

Hardness of deposit

Depending on degress of blackening excellent to sufficient

Max. coating thickness

approx. 0.7 μm


  • Perfect electrolyte for dark to black decorative layers
  • High abrasion resistance
  • Layers up to 0.7 μm possible
  • Suitable for rack plating


  • Jewelry
  • Watches
  • Spectacle frames
  • Writing implements
  • Accessories


  • Produktblatt-rhoduna-471-black-en-screen-20190719.pdf

Your contact person

Markus Legeler

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

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