Which whale species produces spermaceti oil?

The sperm whale produces spermaceti oil, a waxy substance historically recovered from the large spermaceti organ in its head. Despite the name, spermaceti is not sperm or semen; early whalers misunderstood its appearance and coined the misleading term.

Spermaceti consists mainly of wax esters and was prized during the whaling era for making bright, nearly odorless candles and for producing a stable lubricant. Sperm oil remained fluid at relatively low temperatures, making it especially valuable for precision machinery, clocks, and other equipment.

The sperm whale is the largest toothed whale and can dive to remarkable depths while hunting squid. Scientists think the spermaceti organ helps focus its powerful echolocation clicks, although its exact biological functions have been debated. The whale’s enormous head is therefore both a defining physical feature and the source of its historic commercial importance.

A common mix-up is confusing spermaceti with ordinary whale oil, which was rendered from blubber. Modern commercial use of genuine sperm-whale oil is prohibited or heavily restricted under international conservation law.