Burgundy lambskin CASATI leather mules from NICHOLAS KIRKWOOD featuring faux-pearl detailing, gold-tone hardware, pointed toe, low block heel and V-shape vamp. POSITIVELY CONSCIOUS: This Planet Conscious product is crafted with leather that has been produced in an audited and certified Leather Working Group (LWG) tannery — scored according to a three-tier system. The LWG assesses and certifies leather manufacturers that reduce the environmental impact of production..