Cookware materials compared

Almost everything follows from two numbers

Cookware writing is full of adjectives — responsive, forgiving, versatile — that are all downstream of measurable properties. Two of them do most of the work.

The first is thermal conductivity: how fast a material moves heat sideways. Copper is 401 W/m-K, aluminum 237, cast iron around 50, carbon steel around 45, and type 304 stainless 15 to 16. A material that conducts badly develops a hot spot exactly where the flame is. A material that conducts well spreads the heat out across the whole base.

The second is mass. Heat is energy, and a heavy pan stores more of it. Two pans at the same temperature behave completely differently when you drop cold food in: the heavy one barely changes temperature, the light one plummets. That is why a 5.66 lb cast iron skillet sears better than a 3 lb clad pan even though the clad pan conducts better.

Every recommendation on this site is one of those two facts wearing different clothes. Conduction gives you evenness and responsiveness. Mass gives you searing power and stability. You cannot have both maximized in the same pan, which is why a kitchen has more than one.

Clad stainless: the default, and why

A clad pan is stainless on both faces with aluminum in between. That layering exists purely to work around stainless's conduction problem while keeping its advantages, which are considerable: it does not react with acid, it does not care about metal utensils, it survives dishwashers, and it has no coating to wear out.

Get this material right and it is genuinely permanent. All-Clad's D3 is rated oven and broiler safe to 600F and carries a limited lifetime warranty; the failure mode on a clad pan is rivets, not the pan. Its one real weakness is release: bare steel is chemically sticky to protein, which is why food sticks to stainless and why the preheat matters so much.

Buy it if you want one material to build a kitchen around. Do not expect it to cook an egg without fat, or to sear as hard as iron.

Cast iron: a heat battery, not a general-purpose pan

Cast iron conducts poorly and weighs a great deal, and both of those are the point. It takes five to eight minutes to heat evenly and then holds that heat through anything you put in it. Nothing at the price sears better.

The costs are honest and worth stating. A 10.25-inch Lodge skillet is 5.66 lb empty. Bare iron is reactive, so long acidic cooking tastes metallic and strips seasoning. And it is slow to respond, so it is a bad choice for anything where you want to pull the heat back quickly.

Seasoning is not a coating in the nonstick sense. It is oil polymerized onto the metal, and it is repairable forever — a rusted skillet can be stripped and brought back, which is not true of any coated pan. Lodge publishes the method openly. See the cast iron hub.

Carbon steel: the same metal, formed differently

de Buyer publishes its MINERAL B PRO body as "Iron 99%, Carbon 1%", which is chemically close to cast iron. The difference is entirely in forming: cast iron is poured and must be thick; carbon steel is rolled to 2 to 3 mm and is strong at that thickness.

The result is a pan that conducts about the same and weighs about half. de Buyer's 11-inch at 3 mm is 4.6 lb against a comparable cast iron skillet nearer 7 to 8. It also has sloped sides, so you can toss food, which straight-sided iron resists.

What you pay for that is maintenance. Carbon steel rusts overnight if left wet, has a thinner seasoning layer than a decade-old iron pan, and is at least as reactive. Full comparison in cast iron versus carbon steel.

The coated pans: PTFE and ceramic

Both are aluminum pans with something sprayed on. The aluminum does the conducting — that is why coated pans heat quickly and evenly — and the coating does the release.

PTFE is a fluoropolymer, authorized for food contact under 21 CFR 177.1550, and the FDA states that "studies show negligible amounts of PFAS in this coating can migrate to food." It releases better and lasts longer than ceramic. It is also a PFAS, which some buyers rule out on environmental rather than direct-exposure grounds, and that is a coherent position.

Ceramic is a sol-gel silica coating. GreenPan publishes that its Thermolon is made "from sand-derived raw materials, Silicon Dioxide (SiO2)" and is PFAS-free, PFOA-free and free of lead and cadmium, with the coating rated to 850F. It releases beautifully when new and, in general use, declines faster than PTFE.

Neither publishes a lifespan. Not one manufacturer, in either technology. Treat both as consumables — the full argument is in the nonstick and ceramic hub.

Bare aluminum: wrong for pans, right for bakeware

Aluminum conducts at 237 W/m-K, second only to copper among practical cookware metals, and it is cheap and light. It is also soft, reactive with acid, and not magnetic, so it does not work on induction at all.

That combination rules it out as a bare cooking surface and makes it ideal for bakeware, where you want even browning, do not usually cook acid directly on the metal, and never put the pan on a hob. A bare aluminum half sheet with a steel rim is the professional standard for exactly these reasons. See sheet pan materials compared.

What this adds up to

A kitchen built on this reasoning has clad stainless as its spine, one heavy pan for searing, one coated pan for release, and aluminum for the oven. Four materials, each doing the thing it is physically good at, none asked to do a job it is bad at.

That is the whole thesis of this site, and it is why the buying pages recommend what they do. From here, go to what cookware you actually need for the shopping list, or into a material hub: stainless, cast iron, carbon steel, nonstick and ceramic, bakeware, or cookware sets.