Every manufacturer of cast iron skillets will be quick to tell you that their pieces of cookware are compatible with induction cooktops.
And, though that’s generally true, they forget to mention one crucial detail: the fact that cast iron, when used on glass-ceramic surfaces, can cause scratches.
As an owner of an induction cooktop and a user of cast iron cookware, I’m about to tell you all you need to know on the topic and share with you a few options for how to keep those scratches to a minimum.
So, why does this happen in the first place?
Though cast iron skillets are induction-compatible, their rough and porous bottoms can easily scratch the glass-ceramic surface of your induction cooktop. A better choice of cookware would be induction-friendly stainless steel or non-stick.
To understand why that is, we need to look at how induction cooktops work in the first place.
Gas and electric stoves transfer heat to your pans and pots by burning a flame or heating an electric coil under them.
Induction cooktops work differently: they heat your cooking vessels directly by creating a magnetic field below them that’s powerful enough to cause the particles that they contain to vibrate intensely. That vibration creates friction, and the friction creates heat.
By now, you probably know that only ferromagnetic pieces of cookware—pans and pots that contain enough iron for a magnet to stick to them tightly—work with induction ranges.
Of course, there are exceptions to the rule.
Technically, you could place an iron disc, also known as an induction adapter plate, under a non-compatible cooking vessel so that it conducts heat to it. But, to me, this is a workaround and not necessarily a solution. It defies the purpose of having an induction cooktop in the first place!
At first glance, cast iron skillets and induction ranges seem like a match made in heaven. After all, cast iron skillets are made from iron, so they’re as ferromagnetic as cookware gets, right?
But there’s more to it than that.
Present-day induction stoves have a cooking surface made of glass-ceramic, a translucent material with a similar chemical composition as glass that sports the heat resistance and overall toughness of ceramic.
As sturdy and long-lasting as glass-ceramic surfaces are, they come with one major drawback: they’re prone to scratching, especially if you cook with pans and pots made of non-smooth metal.
Cast iron skillets are made by pouring molten iron into casts made of sand. Unfortunately, they fit that description perfectly.
If you own an induction cooktop, does that mean you shouldn’t use cast iron cookware at all?
How to Protect an Induction Cooktop From Scratches
I’m a proud owner of an American-made Lodge skillet and a grill pan myself, and I wouldn’t trade them in for anything in the world.
As much as I’ve tried (and I do test out a fair share of pans and pots for the product picks and buyers guides that I publish on this blog), I can’t get the same browning on a thick-cut steak, burger patty, and salmon fillet when I use cookware made of any other metal.
To keep your cast iron skillet from scratching the surface of your induction cooktop, avoid moving it around too much or simply place a scratch protector mat between them.
Cooking carefully sounds like a good enough solution, but it’s easier said than done.
Suppose you just equipped your kitchen with an induction cooktop, and you’re coming from an electric coil or gas stove. It will take you a while to get used to being more careful.
The general rule of thumb is to keep your cast iron skillet in place, not tossing foods with it and trying to stir as gently as you can so that it doesn’t move all over your cooktop’s glass-ceramic surface.
This is hard but doable. Cast iron skillets weigh a lot. They’re heavy on the wrist, so they’re not the best choice for sautéing thin-sliced meats or vegetables anyway. They stay in place pretty well, so you’ll need to put in a lot of effort to make them move when you stir your foods in them.
Still, if cooking is less like meditation and more like exercise to you, and you have no problems tossing foods in a cast iron skillet, maybe you’d want to consider buying a scratch protector mat, like this one.
What Is a Scratch Protector Mat?
True to its name, a scratch protector mat is a disc-shaped silicone mat that you place between your induction cooktop and your cast iron skillet when you cook with it. Used correctly, it keeps the skillet from sliding and prevents it from scratching your cooktop’s surface.
But use with caution. As with most kitchenware made of heat-resistant silicone, these mats are typically safe to use at temperatures no higher than 480°F (249°C). Cast iron has the tendency to get scorching hot, especially when being preheated. So you could end up burning the silicone mat and leaving marks on a brand new cooktop…
To be safe, never cook on high heat (and avoid medium-high heat for prolonged periods of time) when cooking with a cast iron skillet and a scratch protector on your induction cooktop.
Since I use my cast iron skillet to sear meats—and searing is done at medium-high heat—now you get why I personally don’t use one. However, I do know people who do, and are happy with theirs.
Another thing you need to know about these mats is that they can make using your cooktop noisier. An induction cooktop won’t make any noise by itself, but the vibrations it triggers in the particles of your cookware can often generate loud buzzing or humming noises.
For some reason or another less relevant to the topic of this post, these silicone mats tend to amplify that noise. Which, again, could be a no-no for some readers.
Cast iron skillets are safe to use on induction cooktops. But their rough and porous bottom can easily scratch their glass-ceramic cooking surface.
There’s no solution per se, but there are two workarounds:
One is to be more careful when cooking with cast iron in general, and avoid moving the skillet around as you stir the food in it.
The other is to get a scratch protector mat and place it in-between the surface and the skillet. But this only works on low to medium heat.
Needless to say, everything I’ve written in this post applies for cast iron Dutch ovens, too.
What can I tell you… risks of the trade! At the end of the day, appliances are there so that you can use them. If you’re okay with the occasional scratch on your stove, maybe this won’t even be a problem for you in the first place.