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A piece of dark aloeswood, heavier than ordinary wood, with oily veins running along the grain. Agarwood is one of the most expensive aromatic materials, and one of the most tightly controlled in trade. This piece does not use agarwood. It splits the agarwood smell into four pieces, then looks for the matching piece in the essential oil cabinet.

Four pieces of an agarwood smell

An uninfected aloeswood tree gives pale wood with almost no characteristic smell. Agarwood forms only when the wood is infected by fungi and the tree secretes resin around the wound over many years. The smell of agarwood is therefore the smell of a process, not of a species of wood.

In Vietnam the main species is Aquilaria crassna, listed by the IUCN as critically endangered. Since 2004 every Aquilaria species has been in CITES Appendix II, meaning international trade must be strictly controlled. Vietnamese agarwood now comes mostly from plantations. According to the library page, agarwood oil costs ten to fifteen times as much as jasmine extract.

In perfume names, agarwood usually appears as oud. The library page lists a few bottles with agarwood as the main note: Tom Ford's Oud Wood of 2007, Byredo's Oud Immortel of 2010, Guerlain's Oud Essentiel of 2017. Given the price and the rules on this material, an oud accord can also be built from other materials, as this piece tries to do in the sections that follow.

To build an agarwood smell without agarwood, this piece divides it into four pieces. Wood: the dry, warm, lasting part. Resin: the balsamic, slightly bitter part. Earth and leather: the dark part, rooty, with a faint animal edge. And a trace of ferment, the part that sets agarwood apart from every other wood. This division is a working tool, not a chemical analysis.

The chemistry of real agarwood is quite different. Its characteristic constituents are chromones such as 2-(2-phenylethyl) chromone, together with guaiane-type sesquiterpenes such as oxo-agarospirol. No other oil carries exactly these molecules. The aim here is therefore not to reproduce but to suggest.

Wood: sandalwood and cedarwood

Sandalwood heartwood needs more than thirty years to build up enough oil; trees of sixty to eighty years give the best wood. East Indian sandalwood oil holds alpha santalol at 46 to 60 percent and beta santalol at 20 to 29 percent, giving a warm, creamy, milky, balsamic wood that lasts.

Sandalwood also has a supply problem. Overharvesting from colonial times to the late twentieth century nearly exhausted wild sandalwood in India. Supply now comes mainly from managed plantations, especially in Western Australia. The library page gives a maximum dermal level of 2 percent, because of a rare photoallergy risk.

Hoàng đàn, the name Lê Mai uses for cedarwood oil, gives the drier part of the wood. If sandalwood is a creamy wood, cedar is pencil wood, straight and clean. In the SFP classification the Woody family carries the code E, and the SFP describes it through those two poles: warm, rich notes such as sandalwood and patchouli, sometimes dry notes such as cedar.

In an agarwood accord, wood is the easiest part. These two woods give body and length, but not darkness. Real agarwood has a depth that clean wood lacks; that part has to come from resin and earth.

Resin: myrrh and frankincense

When myrrh bark is cut, a pale yellow sap flows out and hardens in the air into reddish brown lumps. Frankincense does the same, with a lighter resin. Both belong to the Burseraceae family, the same family as elemi and palo santo.

Myrrh oil is distilled from the dried resin, with a yield of about 3 to 8 percent of the resin weight. Its main constituents are furanoeudesma-1,3-diene and furanodiene. It smells warm, resinous, slightly bitter, balsamic and woody. That is the bitterness agarwood has and clean wood lacks.

Frankincense is more complex because several Boswellia species with different chemistry are in use. B. frereana is rich in alpha pinene, B. papyrifera in octyl acetate, B. sacra comes in alpha pinene or limonene chemotypes. Commercial labels often leave the species unclear. In an agarwood accord, frankincense gives the bright part of the resin, slightly lemony, slightly smoky, lifting the myrrh.

Myrrh carries one important contraindication. The library page records myrrh as strictly contraindicated in pregnancy and breastfeeding, by all routes, because of furanodiene and beta elemene. This applies to the blend below.

Earth and leather: patchouli, nagarmotha

Patchouli leaves are picked, dried and lightly fermented before distillation. That fermentation step is why patchouli oil smells earthy, woody, warm, deep and balsamic, with a faint camphor note. Indonesian patchouli, especially from Sumatra, has the highest patchouli alcohol content, 28 to 33 percent. Indian and Vietnamese patchouli are also produced in significant amounts; Chinese patchouli is cheaper, with lower patchouli alcohol, 17 to 32 percent.

Patchouli is the most important piece of the agarwood accord. It carries both the earth and the ferment, the two hardest pieces to find. Patchouli oil also changes with age: the library page records that it improves over time, up to ten or twenty years, and oil aged five to ten years is preferred to new oil.

Nagarmotha, also called cypriol, is the root of the sedge Cyperus scariosus, which grows wild in India. The oil, distilled from dried rhizomes, gives a woody, earthy, lightly sweet smell that the library page describes as not replicated by any other oil. In the agarwood accord, nagarmotha gives the rooty part and a dry leather.

Coffee adds the last piece. A CO2 extract of roasted coffee beans holds guaiacol and 4-vinylguaiacol in traces, for smoky and spicy notes, with pyrazines for a roasted note. The darker the roast, the more smoke and bitterness in the extract. A little coffee gives the agarwood accord a darkness close to its fermented part.

The Lê Mai agarwood blend

Nine drops of patchouli, six of myrrh, six of cedarwood, three of sandalwood, three of frankincense, two of nagarmotha, one of coffee. This blend is a perfume oil, not an alcohol perfume. Coffee CO2 extract contains oil and may haze in ethanol, so the base chosen is jojoba.

Patchouli is the axis, close to a third of the blend. Myrrh and cedarwood take a fifth each, one bitter resin, one dry wood. Sandalwood and frankincense take a tenth each. Nagarmotha and coffee are traces, enough to give the rooty part and the dark part.

The strength is 15 percent in jojoba: 1.5 ml of oil in a 10 ml bottle, about 30 drops. This is the strength of a perfume oil applied in small dots, not an oil for the whole body.

The first plan included a trace of Ceylon cinnamon. The library page gives cinnamon bark oil a maximum dermal level of 0.07 percent, based on cinnamaldehyde; IFRA limits cinnamaldehyde to 0.05 percent in leave-on products. One drop in a 10 ml bottle is already 0.5 percent, seven times the limit. Only in a 100 ml bottle would one drop fall below it. The blend therefore leaves cinnamon out.

The limiting oil is sandalwood: a 2 percent maximum dermal level according to the library page. Here sandalwood is 10 percent of the blend, about 1.5 percent on skin. Patchouli sits at about 4.5 percent, with no IFRA limit. Myrrh and cedarwood sit at about 3 percent, frankincense at about 1.5 percent; these pages give no specific dermal limit.

Nagarmotha has limited safety data, and the library recommends low dermal concentrations; here it is about 1 percent. Coffee extract has no dedicated IFRA Standard; here it is about 0.5 percent. Cinnamon bark was dropped because its 0.07 percent limit cannot be met with one drop in a 10 ml bottle.

Myrrh is strictly contraindicated in pregnancy and breastfeeding; nagarmotha is also not recommended in those situations. Patchouli has some reports of mild phototoxicity at high concentration, so avoid sun-exposed skin. Try it on a small patch of skin before wider use.

Why it is still not agarwood

Put together, the four pieces give a dark smell of wood, resin and earth. On a blotter it suggests agarwood the way a sketch suggests a painting. The chromones of real agarwood are absent, and no other oil can bring them in.

Real agarwood also varies with its source. Steam-distilled oil and a CO2 extract from the same wood already give two different smells. Agarwood oil is produced in Vietnam, Laos, Cambodia, Bangladesh and India, from more than one Aquilaria species. A fixed accord captures only one point in that range.

Yet the accord has one thing real agarwood lacks: it asks for no more aloeswood trees to be cut. For a species listed as critically endangered, that is reason enough to build the agarwood smell from other materials. The piece on Vietnamese agarwood tells the story of the real wood.

The accord also opens in other directions. Add vanilla and warm resins and it moves towards the amber family, as the piece on amber describes. Add more coffee and it turns darker and drier, closer to the roast.

An agarwood smell built from things that are not agarwood.

The gap between the two belongs to the aloeswood tree, and to time.