Aldehyde C-9

Say itAL-dih-hyde SEE-NYNE

Waxy orange peel with a rosy, fatty-floral petal nuance.

What it is: A molecule made in a lab.
Where it comes from: occurs in citrus oils and rose
When you smell it: Top notes: when you spray it.
What perfumers do with it: Aldehydic sparkle for top notes; a trace gives roses a dewy, just-picked petal effect.
Worth knowing: Traces occur naturally in Damask rose oil, which helps explain its rosy side.
Also called: Nonanal; pelargonaldehyde

Not on the label of any of the 1080 perfumes read so far.

Sources