Due to the fragile nature of the stones, we do not offer a warranty on the stones. This is standard industry practice. However, should your oven arrive with a broken or cracked stone, please contact us immediately.  Unfortunately, we cannot replace stones that have small chips in them. Because these stones are handmade, air dried & then kiln dried, it quite often results in imperfections and chipping along the edges. These chips do not alter the performance of the stone or oven, therefore are not considered a defect. If a customer finds chips on the stone bothersome, we recommend rotating the stone when possible to achieve the smoothest surface or touching up the edge with sandpaper.