I bought a pizza stone last summer. I read somewhere that it takes oven heat so well that you can leave it in the oven at all times, even if you're using the oven and not necessarily the stone. Yesterday afternoon I was making a couple of pies in my oven and as I was peering in through the glass vision panel, I watched my pizza stone crack! It split into two pieces with a pie blazing away on it. It was a ceramic pizza stone. I thought it was virtually indestructible! No?