Castoreum Absolute is a unique compound derived from the scent glands of beavers, specifically from the castor sacs located near their tail. Despite its animalic origin, pure castoreum has a musky vanilla aroma, making it a sought-after ingredient in perfumery. To obtain castoreum, the sacs are dried for years before being processed using solvent extraction, creating a resinoid. The compound is then typically ground and mixed with ethanol or carrier oils for use in perfumes.

The scent profile of castoreum is complex and rich, featuring musky, amber, animalic, fruity, and vanilla notes with hints of birch tar and leather, adding sensuality to fragrances. It blends well with ingredients like rose, oud, chypres, and oriental scents. Castoreum is also a highly effective fixative, enhancing the longevity of other perfume notes. Classic fragrances such as Shalimar and Chanel Antaeus have featured castoreum for its depth and richness.