The term “lippage” as used in the stone industry, is the planar offset of the finished surfaces of two adjacent stone units. Due to the relatively tight seams used in countertop installations, even minor amounts of lippage are noticeable. Lippage may be unavoidable due to permanent warp in the slab stock. There should be no detectable lippage at the front or rear edge of the countertop. Maximum lippage at the center of the countertop is 1/32” (0.8 mm).