Last updated: 2026-05-27 | Author: Liang Wei, Compliance Lead, SilkwayOud | 9 years working with Guangdong CITES authority
Quick answer: Use seven simple checks before paying for any agarwood: (1) water sink test for density, (2) burn test for resin pop versus plastic crack, (3) 4-hour patch test on skin for scent evolution, (4) oil viscosity (real oud is honey-thick), (5) country-of-origin paperwork, (6) CITES permit number, (7) price-per-gram reality check. Pass five of seven and you have a strong case.
Synthetic oud is sophisticated now. The molecules are good. Iso E Super and Cetalox can fool first-time buyers in a side-by-side blind. But synthetics fail under structured testing. Here are the seven tests we run on every batch before it ships, and the same ones you can run on yours.
Test 1: The water sink test (chips and nuggets only)
Drop the chip into a glass of room-temperature water. Sinking-grade agarwood sinks within 10 seconds. Standard grade sits halfway. Floating grade floats. Anything that bounces or skips is wax-coated wood, not resin.
Test 2: The burn test
Light a small corner with a flame. Real agarwood resin "pops" softly and releases a layered scent (sweet then woody then smoky). Synthetic gives a sharp plastic crack, melts visibly, or smells acrid like burnt rubber. If it drips a clear liquid, it is wax. If it leaves black plastic residue, walk away.
Test 3: The 4-hour skin patch
Apply one drop on the inside of your wrist. Smell every 30 minutes for 4 hours. Real oud evolves through three phases: opening (sharp, sometimes funky), heart (sweet honeyed wood), dry-down (powdery, soft, lingering). Synthetic oud stays linear. It smells the same at hour 4 as hour 1.
Test 4: The oil viscosity check
Tilt the bottle slowly. Pure oud oil moves like cold honey. It clings to the glass and leaves a slow-running ring. Diluted or synthetic oud runs like water. If you can see the meniscus break in under 2 seconds, dilution is high.
Test 5: Country-of-origin paperwork
Ask for the country of origin certificate. A legitimate seller has this on file. The certificate names the species in Latin (Aquilaria sinensis, malaccensis, etc.) and the export province. "Imported from Asia" or "Oriental wood" with no specifics is a flag.
Test 6: CITES permit cross-check
Every legal cross-border oud shipment has a CITES Appendix II permit number. The format is country code + year + serial (CN-2024-00123). Read our full CITES guide for how to read the permit. Sellers who refuse to share the permit number are grey market or fake.
Test 7: The price-per-gram sanity check
| Format | Real minimum price | Below this = likely fake |
|---|---|---|
| Heating chips (Grade A) | $15-30/g | <$10/g |
| Sinking-grade nugget | $300/g | <$150/g |
| Pure oud oil | $40/ml | <$15/ml |
| Attar (oud + sandalwood base) | $30/ml | <$10/ml |
For verified comparison, look at our Grade A Heating Chips and Royal Maoming Pure Oud Oil.
Frequently asked questions
Can I do all 7 tests at home?
Yes. The water and patch tests need no tools. The burn test needs a lighter and a steel plate. The other four are paperwork or visual.
What if my oud passes 6 of 7 tests but fails one?
Common. A floating-grade real oud will not pass the sink test but is still real. The question is which tests it failed. Failing burn and viscosity = likely synthetic. Failing only sink = likely real but lower grade.
Are AI scent-detection apps reliable?
Not yet. The chemistry between real and well-made synthetic oud overlaps enough that consumer apps misidentify roughly 30% of the time. Stick with the physical tests.
Should I ask for a sample first?
Always, on purchases above $200. SilkwayOud ships 0.3g sampler chips for $9 with shipping refunded against your full order.
Related reading: CITES Certification Guide | What Is Aquilaria sinensis? | Why Is Oud So Expensive?