The worlds of leather and fragrance are intertwined to begin with; what we think of as the scent of leather isn't the dank, decaying smell of stripped and treated animal hides at all, but rather the perfumed components that have been used for centuries to mask and commingle with its true scent. In modern perfumery, those notes are typically rendered from natural non-animal sources like birch tar and styrax, or synthesized with compounds created in a lab.