What is a nonreactive saucepan?!
Non-reactive sauce pans do not react with acids. They can be glass (pyrex, corning ware), enameled cast iron, ceramic, as well as stainless steel. Stainless steel conducts heat more effectively, but this also implies which your food will cool faster. Glass as well as ceramics & enameled cast iron, on the other hand, do not conduct heat well, take a extended time to heat up, but will retain heat longer.
If you punch it and it does not hit back, it's a nonreactive saucepan. DUH. Winning