The thread about convection oven and induction hobs reminded me of something I've been wondering since the spring, which is when induction hobs entered my life. Someone please edumacate me about stainless steel.

We have All-Clad cookware that we've had since the early 90s. All of them work on the induction hob except for one piece: the pasta pot. I confirmed that it's not ferromagnetic because a magnet doesn't stick to it.

I realise that stainless is an alloy and comes in a variety of mixes, but doesn't it always include a fair bit of iron? I can prolly Google this, but where's the fun in that?

Also, what I find striking is that All-Clad used different alloys for different products or simply at different production lots. Despite their claim about their construction being very efficient in terms of heat conductivity, the pasta pot in question was always a bit shit in that regard -- it took ages for the water to boil whether over gas or electric hobs.

Anyway, I'm just mystified by this non-ferromagnetic stainless steel piece.