GC-MS Report: How to Read It (and What It Tells You)

FOREZA · Agarwood Education · Lab Verification · For B2B Buyers

By FOREZA Master Grader · 2026-06-05 · 10 min read · Agarwood Education

A GC-MS (Gas Chromatography–Mass Spectrometry) report is the most definitive lab verification of agarwood authenticity and grade. For high-value B2B purchases ($1,000+ USD), a GC-MS report is the standard expectation. This guide explains what a GC-MS report contains, how to read the chromatogram, what the major peaks mean, and how to use the report to verify that the wood you received matches the wood you were quoted.

What is GC-MS?

Gas Chromatography–Mass Spectrometry is a two-stage analytical technique that separates, identifies, and quantifies the volatile compounds in a sample.

Stage 1: Gas Chromatography (GC)

The sample is vaporized and passed through a long, thin column (the "column") lined with a chemical coating. Different compounds travel through the column at different speeds based on their chemical properties — lighter and more volatile compounds exit the column first, heavier and less volatile compounds exit later. The output of this stage is a chromatogram: a graph of detector signal vs. time, with each peak representing a different compound (or group of compounds).

Stage 2: Mass Spectrometry (MS)

As each compound exits the column, it is ionized and analyzed by the mass spectrometer. The mass spectrometer breaks the compound into fragments and measures the mass-to-charge ratio of each fragment. This produces a unique "fingerprint" that can be matched against a library of known compounds. The combination of retention time (from the GC) and mass spectrum (from the MS) is what makes compound identification reliable.

What the Output Looks Like

A GC-MS report typically contains:

• Chromatogram: a graph with retention time (x-axis, in minutes) and detector signal (y-axis, in arbitrary units or counts). Each peak is a compound.
• Peak table: a list of each peak with its retention time, area (proportional to concentration), and identified compound name.
• Mass spectrum for each major peak (often included as an inset or appendix).
• Method parameters: the GC column type, temperature program, MS ionization method, and library version used for identification.

The Key Compounds in Agarwood

There are hundreds of volatile compounds in agarwood, but the following are the most diagnostic for Kyara authentication.

What to Look For in a Kyara GC-MS Report

Five indicators separate an authentic Kyara GC-MS report from a fake or mislabeled one.

Indicator 1: High Agarofuran Concentration

Authentic Kyara shows a notably high concentration of agarofurans relative to the total chromatogram area. Plantation wood, even if force-inoculated, shows 5–10x lower agarofuran concentrations. If the report shows low agarofurans, the wood is either low-grade or treated.

Indicator 2: Presence of Jinkoh Compounds

Jinkoh-eremol and jinkohol are present in measurable amounts only in true Kyara. Their absence (or trace-level presence) is a strong signal that the wood is not authentic Kyara, regardless of the seller's claim.

Indicator 3: High Sesquiterpene-to-Phenyl-Ketone Ratio

A well-aged Kyara has a high ratio of sesquiterpenes (deep wood) to phenyl ketones (sweet honey). Plantation wood has the opposite — high phenyl ketones, low sesquiterpenes. The ratio is one of the most quantitative indicators of age and grade.

Indicator 4: Multi-Layered Aroma Profile (in the Library Match)

The library match for the overall sample should show multiple compound classes contributing — not just one or two. A "flat" chromatogram with only phenyl ketones and no agarofurans is a red flag.

Indicator 5: Absence of Synthetic Fragrance Markers

Fragrance-soaked wood shows peaks from synthetic oud accords (Cashmeran, Iso E Super, Georgywood, Galaxolide, and others) that are not present in natural agarwood. A trained analyst can spot these immediately. If the report lists any of these, the wood has been treated.

How to Read the Chromatogram

For non-chemists, the chromatogram looks like a series of peaks. Here is how to read it.

The X-Axis (Retention Time)

Time, in minutes, from when the sample was injected. Lighter, more volatile compounds exit first (left side); heavier compounds exit later (right side). For agarwood, the diagnostic compounds typically appear between 8 and 25 minutes.

The Y-Axis (Detector Signal)

The intensity of the detector's response. Higher peaks = more of that compound in the sample. The y-axis unit is usually "counts" or "abundance" and is not directly comparable across labs without normalization.

Reading the Peak Table

The peak table (usually in a separate section of the report) lists each identified peak with its retention time, area (proportional to concentration), and compound name. The total area of all peaks equals 100% (or close to it), and the relative area of each peak is the percentage of that compound in the sample.

For a typical Sinking-grade Kyara, you should see:

• Benzylacetone: 5–15% of total area
• Agarofurans (combined): 15–30% of total area
• Sesquiterpenes (combined): 25–40% of total area
• Jinkoh compounds: 2–8% of total area
• Other compounds: remainder

Numbers outside these ranges warrant further investigation. A very high benzylacetone (>20%) with low agarofurans (<5%) suggests plantation wood or treated wood.

What to Ask For from a Seller

When requesting a GC-MS report from a B2B supplier, specify the following requirements.

1. Per-batch report, not a generic "representative" report. The report should be for the specific lot you are receiving, identified by batch number.
2. Method details: GC column type, temperature program, MS ionization method (typically EI at 70 eV), and library version (NIST 2017 or similar).
3. Full chromatogram, not just a summary table. The chromatogram allows independent verification.
4. Peak table with retention times and areas for all identified peaks.
5. Compound identifications for the 20+ major peaks.
6. Library match scores (typically >80% for confident identification).

FOREZA provides GC-MS reports for all B2B orders over $1,000 USD at no charge. For orders over $5,000 USD, the report is mandatory. For orders over $10,000 USD, we recommend an independent third-party lab confirmation. Email zhangxiaobao217@gmail.com to request a report or to be introduced to a certified testing laboratory in Hong Kong, Guangzhou, or Singapore.

Common Issues to Watch For

Issue 1: A "Generic" Report

Some sellers provide a single GC-MS report for their entire inventory, claiming it represents "typical" Kyara. This is not useful. A per-batch report is the only way to verify the specific lot you are receiving.

Issue 2: A Report That Lists Only a Few Compounds

Authentic agarwood contains 50+ identifiable volatile compounds. A report that lists only 5–10 compounds has either used a poor method or cherry-picked which peaks to report.

Issue 3: A Report Without Method Details

If the report does not specify the GC column, temperature program, and library used, it is impossible to verify the identification. Insist on a full method disclosure.

Issue 4: A Report With Unusual Compound Ratios

If the agarofuran concentration is much lower than expected, or if synthetic fragrance markers appear, the wood is not authentic Kyara. See the indicator list above for specific thresholds.

The Bigger Picture: Lab Verification as Standard Practice

Within 3–5 years, GC-MS verification will likely become a default requirement for B2B agarwood transactions over $5,000 USD, similar to how gemstone certification became standard in the colored stone industry over the past 30 years. The trend is positive for buyers (greater confidence) and for serious sellers (differentiation from fraudsters). FOREZA supports the trend and provides reports as part of our standard B2B workflow.

For the broader context on agarwood authentication, see Agarwood Grading & Authenticity and How to Tell if Agarwood Is Real.

Continue Exploring

• Agarwood Grading & Authenticity (Pillar Page)
• How to Tell if Agarwood Is Real (3 home tests)
• Sinking-Grade Agarwood Test
• 5 Common Kynam Scams
• Sourcing & CITES Ethics
• Wholesale & B2B Partnerships