The Schott Jena glass must be a much harder higher quality than the run of the mill glasstop material used in the USA. I was told that Schott makes all the cooktops in Europe and I had thought they make them for America too-but I guess Corning makes the most for America, although, as Mary Anne said, she bought a stovetop with Schott glass, but she did not say what brand it was.

I use all types of pots, including cast iron which I brought from America, but the most effective are the multi-ply or tri-ply because the heat is distributed evenly over the whole pot--not just on the bottom. If you ask me there is too much heat concentrated on those sandwich bottoms. I do not like them because they burn food too easily.

In Europe the best brand is Spring from Switzerland (too expensive but once used you never want to use any other and you have it for life), and Berndes has started a new line called Berndes TRICION®, and then Rösle has a new multi ply. Is not All-Clad a multi-ply?

I have used copper and copper bottom Revereware on my Schott stovetop with no adverse effect, but I can imagine that is you would let the water boil away or you were to put the burner on and forget to put food in the pot, the copper could very well melt- it is a soft metal. So caution is in order for copper. I also use pots which are not the exact size as the burners, but I use multi ply pots mostly (not always).

I would advise to buy stovetops which employ German made glass from Jena, Germany. As Mary Anne said- Schott.