Gold Chromate Coloring

I have a bolt and a nut. Both are material steel with a cadmium plating. They both have a gold chromate finish. The bolt is a gray
color and the nut is a bronze color. What is added to the gold chromate finish to give it the bronze color?
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Is the bolt also dry film lubed? Fairly common.

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I am not sure if the bolt is dry film lubed. The clear chromate bolt is not corroding, and the gold colored chromate nut is corroding. They are exposed to a severe marine environment, and I thought the gold was supposed to be a better finish than the clear. Strange.

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Chromate coatings normally are green or yellowish green. Moly-disulfide solid film lubrication is charcoal grey. It may or may not have cadmium under it. I would not even bother with a coated bolt in a "severe marine environment." You always damage the coating by installing it. I suggest stainless steel or bronze.

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