Direct answer: Counterfeit incense wood is usually plain timber that has been cooked in oil, loaded with oil under pressure, or soaked in dye and chemicals, then sold as agarwood or sandalwood. Three checks still do useful work — the plume when it burns, the smell it gives off on mild heat, and whether it goes down in water — but they read different properties, so none of them closes the case alone.
Key facts: Everything below is a market heuristic with a long Chinese pedigree, not an analytical method. The only definitive route is a vendor who will state the species and the growing region, backed by laboratory work when the piece is worth the fee.
Key Takeaways
- Four routes produce most fakes: cooking in oil (煮油), pressure injection (高压灌油), soaking in dye or chemicals (泡药水), and passing off an unrelated timber.
- A genuine piece tends to throw a pale plume with a little oil at the edge; treated wood often runs dark and greasy.
- Mild heat separates them further: resin opens in stages, while added oil arrives flat and loud.
- Water tells you about density, and density can be purchased — injection exists to buy it.
- Ask what the wood is, where it grew, and what grade it claims before spending a cent.
The Four Routes, and What Each One Buys
Direct answer: Every treatment is a countermeasure aimed at one specific check, which is why a buyer who relies on a single test is standing where the fake was designed to pass.
| Route | Chinese term | The operation | Check it is built to beat |
|---|---|---|---|
| Cooking in oil | 煮油 | Plain timber is simmered until it takes up oil, weight, and scent | Heft in the hand, casual water test |
| Pressure injection | 高压灌油 | Oil is driven deep into wood with little natural resin | The water test, decisively |
| Dye and chemical soak | 泡药水 | Pale “white wood” is darkened and given a surface smell | The colour grade, a quick sniff |
| Species swap | — | Cheap Lauraceae or Burseraceae timber is scented synthetically | The buyer’s faith in a trade name |
Look at the right-hand column and the pattern appears. Cooking buys weight, injection buys density, soaking buys colour, and substitution buys the name itself. A forger chooses according to what the buyer is likely to inspect, so the countermeasure is never general — it is aimed.
Reading the Plume, the Scent, and the Water
Direct answer: The three field checks are directional, not decisive, and their strength is that they measure different things: combustion, volatile chemistry, and mass.
| Check | What a genuine piece does | What a treated piece often does |
|---|---|---|
| Burning | Thin pale plume, faint oil sheen at the burn edge | Dense dark plume, sometimes greasy or acrid |
| Mild heat | Sweet, shifting, multi-layered; new notes appear as it warms | Flat “perfume” or “charred wood,” one loud note |
| Cold scent | 奇楠 (kyara) is fragrant without heat at all | Synthetic material smells single-note and thin |
| Water | Resin-heavy agarwood goes down (沉水) | Oiled wood may also go down, but smells wrong |
The plume has a mechanical cause worth understanding. Resin-heavy wood burns as fibre plus hardened resin → the resin volatilises fairly cleanly and the fibre smoulders without much soot → the smoke stays pale. Add cheap oil, dye, or chemical residue → those fractions do not volatilise cleanly → they char → the plume turns dark and heavy. Colour is a byproduct of what is in the piece, not a separate signal.
That same chain sets the limit. A careful operator can tune a batch to burn pale, so a clean plume means the material is behaving well, not that it is genuine. Aroma is the harder check to defeat because it asks for change over time: real resin releases in stages as heat climbs, while injected oil tends to arrive at once and then go flat.
The Water Test Has Two Jobs, and They Are Not Equal
Direct answer: 沉香 means “sinking fragrance,” and the name records a real density test. It is trustworthy for rejecting light wood and untrustworthy for confirming heavy wood.
Follow the mechanism one way. Resin is denser than water → wood carrying a high resin load becomes denser than water → the piece sinks → the test has measured density correctly. Now run it the other way. Oil is also denser than water → an operator injects oil to manufacture exactly that density → the fake sinks → the test now reports “heavy,” not “resinous.”
That asymmetry is the useful part. A chip that floats is a strong rule-out: it is not resin-heavy agarwood. A chip that sinks is a weak rule-in: it is heavy, and heavy can be bought. The mistake to avoid is promoting a rule-out into a rule-in — “it sank, so it is real” — because that promotion is the exact behaviour injection is built to reward. The agarwood grading guide sets out the 沉水 bands in full.
An Order of Work That Spends Attention Before Money
Direct answer: The checks have a natural sequence: free questions first, sensory work second, laboratory analysis last. Run out of order, and money gets spent before attention does.
| Step | What you do | What it clears | What it costs |
|---|---|---|---|
| 1 | Ask what the wood is, where it grew, and what grade is claimed | Blunt substitution, vague sourcing | Nothing |
| 2 | Compare the asking price with the claimed grade | Much boiled and dyed material | Nothing |
| 3 | Warm a sliver and smell it in stages | Surface oil, synthetic perfume, scorched notes | Minutes |
| 4 | Burn a small sliver and watch the plume | Dye and chemical soaks | A sample |
| 5 | Send a sample for species and resin analysis | The question itself | Money |
In practice, steps one and two do most of the filtering, and they cost nothing. A vendor who cannot name a species has already failed step one, and no later burn rescues that purchase. The laboratory is not a better version of the earlier steps; it answers a different kind of question, which is why it belongs last and only when the value of the piece justifies it.
Agarwood and Sandalwood Are Faked in Opposite Ways
Direct answer: Both woods are heavily counterfeited, but the fraud targets different properties, so a checklist built for one is close to useless on the other.
| Question | Agarwood (沉香) | Sandalwood (檀香) |
|---|---|---|
| Why it attracts fraud | Top-grade prices, especially 奇楠 | True Santalum album is scarce and slow-grown |
| Usual fake | Injection, boiling, dye | A cheaper Santalum, a pale unrelated wood, a synthetic blend |
| Genuine behaviour | Pale plume, oil seepage, deep resinous sweetness | Mild, sustained creamy-woody warmth |
| Best defence | Density, warmed aroma, vendor | Species confirmation and accepting the price |
Agarwood fraud is an engineering problem about mass and resin appearance. Sandalwood fraud is an identity problem about which tree was cut. Applying “watch the smoke” to a sandalwood purchase checks a signal the fraud never touched, and that mismatch is common precisely because the two materials get lumped together as ” incense woods.” The sandalwood guide covers the species question, and the agarwood incense guide covers the material.
Why the Vendor Question Outranks Every Test
Direct answer: Every physical test assumes you already know what the piece claims to be. The claim is the part a fake disputes, and only the vendor can state it.
A water test assumes agarwood. A burn test assumes agarwood. A warmed sniff assumes agarwood. All three compare material with a claim, and none examines the claim itself. Asking for species, growing region, and grade tests it at the source, for free, before anything burns. A vendor who answers gives you a proposition worth checking; a vendor who hedges has told you something more useful than any burn result.
My own view runs against the usual “spot the fake” list: the strongest signal is not a test at all, it is the vendor. Someone who cannot say what the wood is, where it came from, and how it grades has already answered the question. The burn and aroma checks are the backup, not the verdict. This is the author’s editorial position, not a verified fact.
Price Works as a Veto, Never as a Certificate
Direct answer: A price far below the market for the claimed grade is the strongest reason to walk away. A high price does not mean the piece is genuine, because the fraud exists to capture high prices.
The reasoning runs in one direction. Genuine top-grade agarwood is scarce and costly → a piece offered at a fraction of that level is almost certainly not that grade → the price alone justifies refusing it. Turn it around and the logic collapses: an expensive fake remains a fake, and paying more is what the seller wants. Use price to eliminate the too-cheap piece on sight, then spend the slower checks on whatever survives.
The Label’s Grading Vocabulary
Direct answer: The trade grades agarwood with a short vocabulary — 沉水 for sinking, 半沉 for half-sinking, 奇楠 for kyara — and a label using those words is at least speaking the trade’s language.
沉水 marks resin-heavy wood that goes down in water, the top density band. 半沉半浮 names the middle, partly resinous and mid-priced. Floating wood sits at the low end with little resin. 奇楠 is the structural outlier: oil-rich enough to feel soft, and the most expensive material in the market. For a buyer, a label that says only “agarwood” leaves the grade unstated, which is not the same as having no grade — it means the seller chose silence.
Four Ways Buyers Get Fooled
- Trusting a single signal. Each treatment is built around one check, and that check is the one it beats.
- Reading the water test as proof. It rejects light wood and cannot confirm resin.
- Borrowing the wrong playbook. Agarwood fraud is about density; sandalwood fraud is about species.
- Skipping the vendor. The free question filters more fakes than any burn test.
FAQ
Q: How can I tell if agarwood is real?
Stack the readings and let them disagree. Burned, the genuine article tends to give a thin pale plume with oil at the burn edge; treated timber often runs dark. On mild heat, real resin keeps shifting as it warms, while a fake holds one flat “perfume” note. Density is a third reading, useful for rejection only. The vendor’s willingness to name species, region, and grade matters more than any of them. See the grading guide.
Q: What is “oil-injected” agarwood?
Timber with little natural resin, loaded with oil under pressure so it gains weight and a faint smell. It is built to beat the water test, and it often does. The tell is behaviour under heat: the oil sits in surface pores rather than in resin canals, so it releases fast and flat, then turns harsh, instead of opening in stages. Pair density with a warmed sample. See the grading guide.
Q: Is the sink test reliable?
For mass, yes. For identity, no. Resin-heavy wood goes down and low-grade wood floats, so the test is a fast way to clear poor material. Injection exists precisely to make a heavy piece out of a light one, and dyed wood can sink too. Read a sinking result as “possibly worth testing further,” never as “confirmed.”
Q: Why is fake sandalwood so common?
Because the real thing is slow and scarce. Santalum album needs years to build heartwood oil and has been heavily harvested, so genuine material is expensive. That gap pays for substitution — a cheaper Santalum, a pale unrelated wood, a synthetic blend — and the buyer who shops by name or by the lowest price absorbs the difference. Species and origin, confirmed rather than assumed, are the defence. See the sandalwood guide.
Q: Does a darker colour mean a higher grade?
Only in a piece whose origin is already settled. Resin does darken wood over time, but dye and chemical soaks darken it in an afternoon, and colour is the cheapest property to counterfeit. Treat shade as a supporting detail: warm the piece, watch the plume, and ask where it grew.
Q: Can a fake pass a laboratory test?
Not species identification or resin analysis, which is why most fakes never meet a lab. The treatments here are designed for the checks a buyer runs at home. Analysis separates Aquilaria from an oiled substitute, and it is worth the fee only when the value of the piece justifies it.
Sources
- 本草纲目 — a historical materia medica, recorded as traditional belief rather than clinical evidence.
- Chinese trade and consumer writing on 沉香 checks, including the pale-plume comparison with dyed wood.
- Aquilaria malaccensis on GBIF — the species most agarwood comes from.
- Aquilaria in the CITES species checklist — the listing that constrains supply and invites substitution.
- Research synthesis: docs/research/agarwood-chenxiang-notes.md (R-001).
Related Resources
- Agarwood Grading Guide — how the 沉水 bands are defined, and why fakes target them.
- Agarwood Incense Guide — species and grade, with notes on heating behaviour.
- Sandalwood Incense Guide — the substitution problem told from the sandalwood side.
Natural next step: read how the 沉水 bands are set in the agarwood grading guide, or follow the species question into the sandalwood guide.
Summary
Counterfeits arrive in four shapes — boiled, injected, soaked, and substituted — and each is aimed at a check the buyer already trusts. The plume, the warmed scent, and the water test work as a set because they read different properties of one piece, and the water test in particular must stay a rule-out rather than being promoted to a rule-in. The sequence of work is what makes the exercise affordable: vendor, price, senses, laboratory. Every method here is a traditional heuristic, good for reducing risk and incapable of removing it, and the question that filters more fakes than any test is whether the seller can name the species, the region, and the grade.