&gt; I started by timing how long it took the pans to bring a cup of water to a boil over the maximum gas flame on my stovetop. The copper and the cast iron each took 3 minutes, the aluminum-stainless combination 2.5, and the thin nonstick aluminum just 2 minutes. Light and cheap win for speed.<p>Not sure that&#x27;s the right test... speed isn&#x27;t what you&#x27;re going for.  For example, aluminum foil would very quickly conduct heat straight to the water opposite the flame, rather than distribute it broadly across the surface.<p>Because heat transfers fastest across the gradient where the temperature difference is greatest, foil would win the day even though it&#x27;s a terrible cooking surface.<p>A heavy copper pan would evenly distribute the heat it&#x27;s given to the sides and all over the bottom rather than straight to the bottom.  That&#x27;s kind of the point.