Ash content in coconut charcoal
By Mohamad Sinno, Charcoal Expert · Reviewed by Budi Dharmawan, Head of QC,
Ask AI for an importer brief:
Ash is the figure buyers specify first and the one most often quoted without a report behind it. Three things get called "ash content" in this trade and they are not the same: what a laboratory measured, what a seller claims, and what a contract guarantees. This page separates them.
What the percentage physically is
Ash is the mineral residue left when the carbon has burned away. A laboratory weighs a sample, burns it under controlled conditions, and weighs what remains. The percentage is simply the second weight over the first.
Worked as a hundred grams. Burn 100 g of briquette to completion. If 1.6 g of mineral residue remains, the ash content is 1.6%. At 2.5% you would have 2.5 g from the same 100 g — a little under a gram more, which does not sound like much until it is the sediment a lounge sweeps out of every bowl, all evening, every night.
That is the whole of it. The difficulty is never the arithmetic — it is knowing which sample, which method and which basis produced the number you were shown.
What our reports measured
| Report | Date | Ash | Method for the ash row |
|---|---|---|---|
| Beckjorindo COA 000957 | 17 June 2026 | 1.58% | ASTM D1762-84 (Reapproved 2021) for moisture and volatile matter; the laboratory’s in-house IK.BPL.7.4 for ash (Point 6.3) and fixed carbon (Point 6.4) |
| Beckjorindo COA 000964 | 24–25 June 2026 | 1.34% | ASTM D1762-84 (Reapproved 2021) for moisture and volatile matter; the laboratory’s in-house IK.BPL.7.4 for ash (Point 6.3) and fixed carbon (Point 6.4) |
| Beckjorindo COA 001061 | 23 July 2026 | 1.20% | ASTM D1762-84 (Reapproved 2021) for moisture and volatile matter; the laboratory’s in-house IK.BPL.7.4 for ash (Point 6.3) and fixed carbon (Point 6.4) |
Read across, the measured spread is 1.20–1.58%. Three single samples from one product over some months — not three grades, and not a promise about your container. The full reports, their other parameters and what we never tested are on what our laboratory reports measured.
Measured, claimed, guaranteed
This is the distinction worth carrying into any supplier conversation.
| What it is | What you can do with it | |
|---|---|---|
| Measured | A result found in one named sample, on a named date, by a named laboratory | Verify it with the laboratory. It evidences that sample and nothing else. |
| Claimed | A band on a specification sheet or a website | Ask which report it came from. If there is no report, it is a marketing position. |
| Guaranteed | A ceiling written into a contract, evidenced per shipment by that batch's COA | Enforce it. This is the only one of the three that survives a dispute. |
Our commercial bands each carry an ash ceiling in the third sense — the five bands and what each costs per tonne sets them out with their prices. The tightest is 1.2–1.6% and the widest 2.5–3.0%. Reports measured to date fall within the Diamond band; every tier's ash ceiling is contractual and verified by the batch COA. The acceptance band that applies to your order is the one agreed in your contract.
What the market calls "premium"
Conventions, dated, and none of them a standard — there is no body that certifies a grade name:
- "Premium" clusters at ≤2–2.5% ash, with above roughly 3% treated as standard grade (market convention observed across supplier listings, August 2026).
- Batch-to-batch variance above 0.3 percentage points is described as a process-control signal rather than a defect — a reason to ask what changed (supplier technical explainer, May 2026). It is a useful question to put to any supplier whose consecutive COAs move more than that.
- Sub-2% claims are common and are usually stated without a report. The claim is cheap; the certificate is the thing.
Ash colour tells you nothing
White ash is widely read as a sign of quality and it is not one. Colour comes from the mineral composition of the residue and from how completely it burned, and a pale ash can sit on top of a perfectly ordinary ash percentage. There is no laboratory method that reports colour, which is the practical tell: if it mattered, it would be on the certificate. Specify the number, require the COA, and let the colour be whatever it is.
The other half of the burn
Ash is what is left at the end. What produces the heat, and what produces the smoke at the start, are a different pair — fixed carbon and volatile matter. And what any of these figures proves about a shipment is settled by what a certificate of analysis proves. Ash beside the other three figures, and the basis, method, laboratory and date that make two results comparable, is set out in what each charcoal specification figure actually means.