Не надо маслом, камень нужно предварительно сильно нагревать, представляю сколько чада будет, если его в таком виде маслом смазать
Вот что Гугл говорит
Pizza stone rules:
1) never use soap to wash your pizza stone. I do rinse mine occasionally with water, but never soap.
2) Preheat your stone--this is really the whole advantage of the stone.
Preheat oven (with stone on lowest baking rack) to 450 or 500. Preheat 15 min to 30 min if time (it works better if the stone is truly hot).
Sprinkle cornmeal (to prevent sticking) on a pizza peel (wooden paddle) or cookie sheet (with no edges). Put your dough on the peel and then
decorate as desired. Shake the peel a few times to make sure the dough isn't sticking to the peel.
Now open the oven door and slide the pizza onto the hot stone (this takes a little practice). Your pizza should only take about 10 minutes. When
it's done, slide it back onto the peel, slice and eat!
PIZZA STONES - A baking stone should be placed on the lowest oven shelf and preheated with the oven. Once pre-heated, the stone evenly transfers intense heat to the food being cooked, ensuring a particularly crisply baked base.
As to if it might crack, this I do not know, as I have never had it happen. I always place the cold pizza stone in a cold oven. I then turn on the oven to 400 degrees F. to preheat oven and stone. Once the stone is hot, I do not remove it from the oven. I place the pizza on the hot stone in the oven. Following is my tip that I use when making pizza and using the pizza stone:
PIZZA TIP - A common problem is that the topped pizza sticks to the baker's peel. Giving the peel a quick jerk may work, but it may also jerk your toppings off the pizza as well. A helpful hint is to put a piece of parchment paper on the peel instead of using cornmeal. I place the rolled-out pizza dough on the parchment paper and then add the toppings. The parchment goes into the oven with the pizza. This makes it easier to slide the pizza off the peel and onto the hot baking stone.
CLEANING PIZZA STONES - Think of your pizza baking stone as a sponge; it will soak up everything put on it. These "stones" are actually molded sand, tightly compacted under high pressure. Like sand on the beach, they will suck in any liquid exposed to the surface. Anything else in the water -- including soap -- goes right into the stone. Manufacturers warn you to use only clear, plain water to clean a baking stone.
First, completely submerge your baking stone in warm, clear, plain water for 15-20 minutes. This should thoroughly saturate the stone with clean water and dilute the soap residue. Next, remove the stone from the water and place it on a pie cooling rack on your kitchen counter. Allow the stone to dry completely overnight.
Repeat the same soaking and drying process five or six nights in a row. After the last round, bake some pizza dough on the stone. If the pizza stone still smells, I'm afraid your stone is destined for the trash.