These stepping stone molds are manufactured using thick, durable 75ml polystyrene, ensuring many pours. Your finished stepping stone or wall plaque will be a sturdy 2 inches thick and measure 15-16 inches in diameter and will weigh anywhere from 20-30 lbs, depending on the mold. Using premixed concrete, mortar, stucco or your own custom blend, you can now easily create your own unique stepping stones and decorative wall plaques!