The perfect pizza stone for the perfect pizza. These are not designer stones that look pretty and crack during the first use. Our Pizza Stones are rough and rugged. They are made of a high grade Non-Toxic Mullite mixture, containing a very high quantity of grog. This makes our Baking Stones virtually indestructible and impervious to thermal shock. 100% Guarantee against cracking and thermal shock. If for any reason one of our pizza or baking stones cracks while using it we will replace it!!! These pizza stones are very porous allowing pizza moisture to be absorbed making for a very crispy crust.