Iris.

Iris in perfumery does not come from the flower but from the rhizome (root) of Iris pallida, grown in Tuscany and the Atlas. The roots are harvested at three years, then dried and aged for another three to six years before being distilled into orris butter — a waxy, fragrant solid worth more per gram than gold.

The scent is cold, powdery, almost violet-like, with a buttery makeup-compact warmth underneath. It is the most patient note in perfumery, and the most quietly luxurious.