I know where the question is coming from. I have quite a few air-dry clay packages in my studio that are just sitting there. Some are already open and I am asking myself, every time I see them, how long they might still be usable. I will give you one last chance to turn around because you might not want to hear the answer that I am about to give you in this article. But if you are still willing to know if Air dry clay can get moldy then read on because I am about to give you the answer in great detail.
In short, air-dry clay can get moldy. In fact, there is always some small amount of mold inside air dry clay no matter if it is a new package or an older one. With time the mold content will become more until it becomes visible at which point you should avoid any skin contact.
Don´t be alarmed, even though air dry clay has some small amounts of mold in it this mold is not dangerous at all.
It is completely normal for most air dry clay to have traces of mold in it and in fact that little bit of mold will actually make the clay more workable.
It can take years until a properly closed pack of air dry clay molds to the point of no return.
My oldest package of air dry clay is about three years old now and it is still perfectly fine with no visible signs of mold.
But once you can see mold on the clay in form of black or yellowish spots or areas then you should maybe not touch and use it anymore. At this point, the mold content inside the clay has become so much that any skin contact should maybe be avoided.
You can keep your air-dry clay from molding if you store it properly. If you want to know exactly how to permanently store air-dry clay then consider reading my guide on storing air-dry clay.
Can You Use Air Dry Clay That Has Gone Moldy
It is kind of hard to definitively answer this question because what is considered an air dry clay that has gone moldy? As we just learned, air dry clay always has little amounts of mold in it even if it is very fresh.
So for the sake of giving a straight answer, I will just assume that air dry clay is considered being moldy as soon as you see traces of mold in form of black or yellow discolorations.
You can use air dry clay that has gone mouldy as long as the mouldy parts are just very small. You should also be careful with skin contact depending on how sensitive your skin is. If the mouldy parts of your clay show strong black or yellow discolourations then you shouldn´t use that clay anymore.
That being said, as long as your clay is only slightly moldy you could still save it by mixing some water with a few drops of bleach in the clay. This mixture will most of the time, help to revitalize old clay and make it malleable again as well as neutralizing some of the mold in the clay.
This Is Why Your Air Dry Clay Might Smell Bad
I had quite a few people emailing and asking me if I could help them with their air dry clay because it started smelling really bad after just a few months.
This is something that can happen quite fast with some clays while it will take quite a long time for other clays to smell bad.
Your air dry clay smells bad because it will grow bacteria if it is sitting around for a while. It will also slowly get moldy. This doesn´t affect the clay in any bad way. On the contrary, aged clay is actually better to sculpt with. But it might start to smell bad.
A few drops of bleach mixed with a little bit of water can help you getting rid of the bad smell.
Simply mix it with your clay thoroughly and your clay will start smelling a little bit more like bleach but the bad smell is at least gone.