In 2021 fishermen off Yemen hauled in a crusty 280 pound lump worth $1.5 million: ambergris. It forms when the indigestible chitin beaks of giant squid irritate a sperm whale’s gut and the bile ducts coat them in a cholesterol rich wax, much as an oyster coats sand to make a pearl, and researchers often find beaks inside. Only about 1 percent of sperm whales produce it. Small masses pass with feces, while giant ones may cause a fatal blockage and escape only after the whale dies. Fresh ambergris is pale, smells strongly fecal, and is worthless. Because its specific gravity is about 0.780 to 0.926, it floats for years, and sun and seawater break it down through photodegradation and oxidation into a dense gray or black lump with a sweet, earthy, marine scent.

The name comes from the Arabic anbar via Old French for gray amber, before fossil tree resin took over the word amber. In 1946 chemists Leopold Ruzicka and Fernand Lardon isolated its main component, the odorless terpenoid ambrein, which sunlight splits into the scented compounds ambroxide and ambrinol. Perfumers value it as a fixative that slows evaporation, and it once flavored King Charles II’s favorite eggs, hot chocolate, Turkish coffee, and a rum shrub, while Europeans carried it in pomanders against plague under the miasma theory. Commercial whaling at up to 50,000 whales a year led to the 1982 moratorium. CITES does not cover animal waste, so the UK, France, Switzerland, and the Maldives allow trade, but the US, Australia, and India ban it, and most perfumes now use lab made Ambroxan.

• Fossilized ambergris has been found in marine deposits 1.75 million years old.
• Hunters train dogs, with up to 300 million scent receptors, to find it on beaches.
• The English form ambergrease grew from the substance’s waxy, fatty feel.
• Pre colonial Maori in New Zealand called it mimiha and chewed it.
• Natural ambergris stays pricey as a Veblen good, valued for the improbable story behind each lump.