When it comes to traditional pizza stones, celebrity nutritionist and chef Serena Poon, founder of Just Add Water®️ & Culinary Alchemy®️, says that there are two main material options: ceramic (which is often made out of clay) or cordierite, like the ROCKSHEAT stone. “Cordierite is going to be a better surface when it comes to longevity, but they are sold at a slightly higher price point,” she says. That said, nowadays, the idea of a pizza stone has extended beyond just stone and includes steel and cast iron, too. When shopping for a pizza stone, you’ll want to think about longevity and crust benefits. Generally speaking, cast iron is the most durable and retains the most heat (though we found in testing that it offered more of a bread-like texture than a crisp crust). But if you’re set on a pizza stone, Poon says to opt for cordierite.