Costus

What it is

Costus root is the aromatic underground material of the plant now accepted by Kew as Dolomiaea costus.

Older perfumery, medicinal and trade references commonly call the same species Saussurea costus, Saussurea lappa or Aucklandia costus. Those names are important aliases for historical research even though Kew currently treats them as synonyms.

What to notice

Traditional costus material is associated with an unusual combination of:

• earthy root
• fatty or oily depth
• animalic fur or hair
• leather
• violet-like powder
• warm wood
• slightly medicinal or sweaty facets

It is one of the natural materials that can blur the line between rooty, floral and animalic impressions.

Conservation context

Costus is not just a historically exotic perfume material. CITES lists Saussurea costus—the trade name still used in the Convention—in Appendix I, reflecting strict controls on international trade.

That makes legal provenance and current regulatory status essential whenever natural costus is encountered.

Modern costus effects

A perfume can evoke costus through reconstructed accords without using natural costus root material. In The Aroma Book, a costus-like smell is not enough to establish that regulated natural material is present.