Many of you might have noticed before that brass, along with some other metals, produce a greenish tint from time to time. Typically, you will see this on copper, bronze and yes – even brass.
This is down to a process known as oxidation and it’s a totally normal process that aims to protect the metal from rusting!
Brass turns green but it’s not the only metal that does this. Metals that contain copper will do this, such as bronze and of course copper. When these metals are exposed to oxygen, they begin a process called oxidation.
This process is a normal chemical reaction which is actually just a thin layer of copper oxide forming on the metal’s surface. Over a period of time, the green color becomes much more prominent and obvious.
Underneath the green tint, you might notice a greenish-blue color and this layer is known as patina, which acts as a way to protect the metal from rusting.
The Chemical Reaction
Oxidation, which I have spoken about previously, is when oxygen comes into direct contact with a metal that contains copper – brass being one of them. Brass is an alloy which is devised of 70% copper and 30% zinc.
Indeed, bronze and copper specifically also undergo this process, and some people that use these metals in the household and notice this process get a little worried about it. Luckily though, there’s no need to panic – but it can get a little unsightly.
If you’re hoping to prevent this discoloration, you’ll want to keep your brass clean and dry, and any time that you notice green appearing on brass, you can simply use warm water, a mild abrasive and a soft cloth to get off the copper oxide layer.
Copper Oxide – Good Or Bad?
It’s now a good time for us to explore if copper oxide is a good thing or a bad thing. Well, the process is natural and it’s going to happen which is the first point to note.
However, there are times when copper oxide can be a good thing, and other times a bad thing.
Below, I’ll cover both. I’ll show you when copper oxide might be a good thing and times when it could be an issue.
Copper Oxide – What It’s Good For
There are some times when patina, the result from copper oxide, can be useful.
One of these is simply for aesthetic purposes. Patina color finishes are becoming increasingly more popular for things like door knockers or for mailbox numbers.
Indeed, some people actually prefer the color of brass when it turns into this color from oxidation.
What’s more, as the process acts as a protection for the metal – it can actually protect it from further damage, which is ideal for things like door knockers.
Copper Oxide – When It’s Not Good
Patina can sometimes be unwanted and one of the worst times it can appear is when we’re using electrical wiring, which is usually made from copper.
If these wires become exposed to oxygen and oxidation occurs, the wires can become less conductive in extreme cases.
On top of this, oxidation can even cause electrical shorts to happen. However, it’s not just for electrical wiring when copper oxide can be problematic.
Take plumbing for example, where pipes are often made from copper, bronze or brass.
If these pipes develop patina, it’s possible that the water flow can be affected and lead to things like clogs, which in turn can mean you need to pay out for a professional to fix the problem!
A final problem is simply how it looks. While for some objects, patina can be aesthetically pleasing, other times it can be unsightly and people might want their brass, bronze or copper to remain shiny, like it’s brand new.
Can I Turn My Brass Green?
Of course you can and there’s a few ways you can do this. The first way and perhaps the most simple is by using a chemical patina solution and allowing it to settle.
However, the second way can be done without having to purchase any chemicals.
The second way is by placing your brass item into an airtight container with copper oxide and then wait until you get your desired effect.
Speaking of waiting, you could just wait for your brass to turn green over time without doing anything! It just depends on how long you have to wait really.
How Do I Get Rid Of Green From Brass?
Okay, so there are a couple of things to note here. If your brass has already shown the effects from oxidation, then you can use a soft cloth with warm water and possibly a mild abrasive, depending on the severity.
However, I would urge you to try to prevent oxidation before the green color appears in the first place.
First, try to keep the brass clean and dry, and then if possible, add a sealant to the metal which will act as a shield to the metal from oxygen.
It has also been known for nail polish to work as a sealant from time to time, although I would recommend using real metal sealant instead.
It’s also important to note here that green coloration will occur at some point, whether that is a little or a lot, because it’s a natural process. However, these points will prevent the worst of it.
Yes, brass turns green because of oxidation – but there are ways to prevent its severity if you want to. I hope my guide has been useful for you and you understand more about this topic now!