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Coco Reina

What a certificate of analysis proves

By Mohamad Sinno, Charcoal Expert · Reviewed by Budi Dharmawan, Head of QC,

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A certificate of analysis evidences four things: that batch, that date, that laboratory, that method. It is the strongest quality document in this trade and it is narrower than most buyers assume. Knowing the edge of what it covers is what stops a genuine certificate being read as a guarantee it never was.

Sample preparation
Analytical results are only as representative as the sampling behind them, which is why a retained sample is normally drawn per batch rather than per shipment.

What it proves

That batch The material the sample was drawn from, identified by the batch or report number on the certificate.
That date The condition of the sample when the laboratory received and tested it — both dates are usually printed.
That laboratory A named, accredited body that can be contacted and asked to confirm the report number.
That method The test procedure used for each row, printed per parameter. Different rows can use different methods.

What it cannot prove

The factory A COA describes material, not a producer. A trading company can hand you a genuine COA for charcoal it did not make — check the sample is named to the seller.
The next batch It is evidence about one production run. Consistency between runs is a separate question with a separate answer.
Anything after it lapses Each certificate states its own validity. Past that date it is a historical record, not a current statement.
What was not tested A report covers the rows it lists. Calorific value, burn time and drop test are absent from ours because those tests were never run.

The second row is the one that costs money. A sample batch arriving to specification is evidence about that sample batch — it is not a promise about month six. What carries across runs is the contract band and the batch COA that proves each shipment against it, which is what batch-to-batch consistency actually means.

Weathering under cover
Weathering is a holding period, not a treatment: charcoal is left to stabilise under cover before it is packed for sea freight, and the IMDG Code makes that period a condition of carriage.

A COA is not a specification sheet

Specification sheet Certificate of analysis
What it states A band the seller intends to hold A result found in one named sample
Who produced it The seller An accredited laboratory
What it covers The product line, indefinitely One batch, for a stated validity period
Weight in a dispute Only what your contract incorporates Evidence of what that batch actually measured

If a supplier answers a request for a COA by sending a specification PDF, that exchange has told you which of the two exists.

Master cartons stacked
The master carton is the unit that customs, the carrier and the buyer’s warehouse all count, which is why its dimensions and net weight drive both the packing list and the container plan.

Our policy

The 3 reports we hold, with their numbers, dates and downloadable copies where we have them, are listed on our document library — alongside an explicit list of what we do not hold. What those reports measured, row by row and method by method, is read across on our quality and specifications overview.

Read one line by line

Header, method column, results table, validity, signature — and the red flags worth knowing: how to read a charcoal COA line by line, walked through on one of our own certificates.

Then two questions that come straight after it. Whether the document is genuine at all — the routes that confirm a lab report without going through the seller, run here against our own three certificates including the one we got wrong. And which document you should have asked for — spec sheet versus COA, and which one proves anything.