I have these rods with rounded ends, originally from a light fixture, with a full golden color of medium brightness and shine. I'd like to use those ends, and perhaps file more semispheres from the material. However, sanding one (to remove circular manufacturing traces), the cleaned material is not only quite light but hardly yellow, almost silvery with just a tinge of color.
What I want is to make it golden again, but not too dark nor dull, though high shine isn't necessary, nor matching the original finish. And while there's the option of finding another alloy, I want to learn about this case.
First I simply let the piece lie around, but this particular stuff hadn't darkened after a few days. (That was in cold, dry weather; current mild conditions actually do the trick. So I'm satisfied, but I let the question stand.) So I put it in water (really the last puddle from a bottle of ozone/oxygen disinfectant which had been standing around for months and smelled no more), thinking that would speed oxidation; yet the result of watering was still light and also actually coppery, shown in the picture.
(This photo doesn't bring out the lightness difference that well. Think of the tip as two notches lighter rather than one; and that was also so before the reddening.)
Then I went to read up on aging brass, thinking that was the material. I don't want to use strong chemicals or buy anything, so the options seemed to be salt sludge, vinegar solution (possibly salted), and coffee or coffee grounds. Yet all those articles aim at a pronounced patina, whereas I just want back a saturated golden hue like the original finish has, though the precise color doen't matter. Hence I'm wondering what to use and how to control the effect, also in relation to the times I'm at the workshop.
- How do I get my gold back? That is, which agent do you recommend,
- and how far to dilute it so that appreciable action will take either up to 3 or 4 hours, or at least 21 hours?
People indicated in comments that the metal might be pot metal or else low-copper brass because it's so bright and doesn't catch fingerprints, neither on the show surface nor nakedly. Density is around 8.6 g/cm3. It feels slippery under saw and file but is tougher than typical brass.
Below's a bulk color comparison after two or three weeks of cold, dry air exposure vs. newly sanded. It had darkened pretty nicely. Note that the bright one isn't quite silver and the copper red shown above is unmistakable I guess.
Update My most elaborate, and prettiest, piece is finally done, after letting it lie a few times out of fear of botching what I had ;)