I want to add a dark patina to a brass compression fitting that I want to use as a lanyard bead. What is the fastest method for doing so? I read that you can achieve it by dipping the brass in lemon juice. I left the thing soaking all day and no change at all. Any tried and true methods out there?
Patina solutions that works on copper will also work on brass. The effects will be slower, and less pronounced, but can be accelerated with heat. This a pair of brass fitting that I filed the hex portions off and patina'd with liver of sulfur and a torch. The fittings are coated, but I just burn the coating off and then apply the liver of sulfur to the still hot metal.
I just blasted the crap out of it with my torch. I suppose a you could go at it with a dremel wire wheel if you wanted.
It may be electroplated, Baldwin Brass hardware goes through several stages of chemical and electroplate to get their finish and it is near bulletproof.
I've read that hard boiled eggs give a heavy patina in a short time. Boil some eggs, put them in a zipper bag (or similar), crush the eggs and throw the brass piece in.
I use water mixed with with "liver of sulfur gel," and it works nicely, darkening the brass. The longer you leave it submerged, the better. It also depends on the brass' copper content. The more copper it has, the darker it gets. I've done a bunch of belt buckles this way. It also works on nickeled-brass, leaving a black haze on the nickel, which gives the piece an aged appearance. Sent from my SM-N920P using Tapatalk
Do keep in mind that if you are going for a patina in its true sense and not a chemical reaction resulting in a darkened surface, you need oxygen as well. A patina is oxidation at its core. Salt solutions or acidic solutions will accelerate the oxidation, but without oxygen the reaction cannot take place. This is why iron submerged in water will not rust as quickly as an identical piece of iron spritzed with water and left in the open air. The same principle applies to brass. I'm no chemist by any means, but the above is accurate to the best of my knowledge- I hope it was helpful; if it was incorrect, I trust that a member more knowledgeable than I will correct it.
@thatotherguy: I think you've described pretty well how oxidation = patina. I was a biochemist back when dinosaurs still walked. Although my professional peers in chemistry will be quick to remind me that in chemical terms 'oxidation' means something quite different, but let's not get too deep in the weeds! Well done! L'chaim! Moshe ben David
After 3 years since the initial post, I assume that the OP had already patinaed his bead. Just sayin'. Good info none the less.