Pizza stone vs pizza steel

Field	Pizza stone	Pizza steel
Material	Cordierite, ceramic, or natural stone	Solid steel plate
Heat transfer	Moderate — stores heat well but transfers it more slowly	High — transfers stored heat to dough much faster
Thermal mass	Lower than steel of a similar size	Higher — recovers heat faster between bakes
Crust result	Good, even bake; less aggressive bottom crisping	Notably crisper, more charred base, closer to a deck oven
Weight	Moderate	Very heavy
Risk of damage	Can crack from thermal shock or improper cleaning	Can rust if not dried and lightly oiled
Typical cost	Usually less expensive	Usually more expensive for an equivalent size

Which suits you

Choose a steel if you want the closest possible approximation of a professional deck oven's bottom heat in a domestic oven, and don't mind the weight and cost. Choose a stone if you want a lighter, less expensive option and are happy with a slightly less aggressive bake.

Sources

Modernist Pizza
The Pizza Lab (column)