Pound for pound, ambergris was the most valuable product produced by the whale. It was—and is—also the rarest and most enigmatic whale product. An opaque, waxy substance from a sperm whale’s intestines, it was found occasionally in the stomachs of whales being processed on whale ships. More commonly, it was found floating on the surface of the world’s oceans or washed up on the shore in pieces that could weigh several hundred pounds. It was used by western cultures as a fixative to prolong the scent of perfumes into the later 20th century.
But why it is formed—and from which end of a sperm whale it is expelled—remains unknown. Fragments of squid beaks are often found inside the pieces, and some scientists believe that ambergris forms around the sharp, indigestible squid beaks to prevent irritating or cutting a whale’s intestines. Others consider it the cetacean equivalent of human gallstones.