Aldehyde C-14

Say itAL-dih-hyde see-for-TEEN

Ripe velvety peach skin, creamy and warm, slightly coconut-like.

What it is: A molecule made in a lab.
Where it comes from: made from undecylenic acid (from castor oil)
When you smell it: Heart: the first hours.
What perfumers do with it: The classic peach note; adds skin-like fruity warmth to chypres and florals.
Worth knowing: Despite the name it is neither an aldehyde nor fourteen carbons long; perfumers kept the historical misnomer.
Known in: Mitsouko (Guerlain, 1919)
Also called: gamma-Undecalactone; peach aldehyde

Not on the label of any of the 232 perfumes read so far.