What Is Oud (Oudh) in Perfumery?

A bottle of oud

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Oud is one of the most expensive and desireable perfume ingredients in the world. It has an intoxicating musky scent that can be quite potent and has been used for centuries in India, Southeast Asia, and the Middle East. Today, many perfumers in the West are using it as a base to create some amazing fragrances for men and women.

What Is Oud?

Oud comes from the wood of the tropical Agar (Aquilaria) tree, a genus that includes 15 different species. The tree is believed to have originated in the Assam region of India, from there spreading to populate Bangladesh and much of Southeast Asia. Wood chips off the trees are often burned as an incense, and it's common for them to be used during religious ceremonies and various celebrations throughout Southeast Asia and the Middle East, including China, Japan, and India.

When the wood of this tree gets infected with a parasitic mold called Phialophora parasitica, it reacts by producing a precious, dark, and fragrant resin. This is the perfume ingredient oud, which is also called agarwood, oudh, agalocha, aloeswood, or eaglewood. Agarwood is a rarity on many fronts. Because the resin is only triggered by the mold, it's estimated that a total of 2 percent of these trees produce it. Not only does this raise the price of the oil, the wood is also one of the most expensive on the market. Additionally, many of these trees are now threatened species.

Oud Oil

The oil of oud can be extracted by distillation from the wood or by melting the resin. It's non-irritating and can be applied directly to the skin. However, the price is the real kicker; Forbes has reported that it can cost $5,000 per pound. Oud retailers often sell just a 3-gram bottle for $300 or more. The same retailers also note that you only need a little oil, so that bottle should last the average daily user an entire year.

Due to its rarity, high demand, and the difficulty of harvesting it, oud oil is perhaps the most expensive oil in the world. The annual oud market is around $6 billion, and its value is often estimated as one-and-a-half times the value of gold. For these reasons, it's occasionally referred to as "liquid gold." The specific value of any particular oud, however, varies depending on the source. Certain tree species produce more valuable oud, and the region where the trees grow is a factor as well. Not to mention, oud that occurs naturally is more expensive than oud produced by an artificial infestation of the mold.

The Scent Itself

Oud (in Arabic oudh) is valued strongly by perfumers for its warm sweetness mixed with woody and balsamic notes. It's an aromatic and complex scent. It is used in the form of oud oil (dehn al oud) or a resin (oud mubakhar). When used in a perfume composition, oud is most often a base note. Essential in every perfume, unlike top notes and middle notes, base notes tend to stay on the skin long after the others dissipate. In a perfume with an oud base, it's likely you'll catch a whiff of it alone hours after applying it.

As with many other expensive perfume ingredients, there are synthetic ouds produced. Compared to the naturally produced fragrance, these are nothing short of a disappointment. Synthetic oud tends to be more leathery and woody—sacrificing its warmth, sweetness, and balsamic notes for the price point.