This page sits under Mulia Charcoal's shisha charcoal quality standards pillar. It owns what each parameter means and what a good value is; the laboratory procedure behind each figure is covered on the testing methods page, linked at each parameter.
These are specs you can test yourself — request a sample
Quick answer
What do shisha charcoal specifications mean?
Each figure on a shisha charcoal spec sheet answers one question: is this good? Lower is better for ash, moisture and volatile matter; higher is better for fixed carbon and calorific value. Those five are measured in a laboratory; burn time and ash color are observed under defined conditions. Our ash runs 1.6–2.8% depending on the grade ordered.
The parameters, defined below
Each value carries its basis in brackets. Each is defined, given a direction-of-good, and benchmarked below.
- Ash content
- 1.6–2.8% by grade (contractual)
- Fixed carbon
- ≥ 75–82% by grade (contractual)
- Moisture content
- ≤ 6% for every grade (contractual)
- Volatile matter
- 7.94–10.93% (measured, grade not stated)
- Calorific value
- ≥ 7,000–7,500 kcal/kg by grade (contractual)
- Burn time
- ≥ 2–2.5 hours by grade (contractual)
1. Laboratory-measured parameters (Tier A)
These five are determined in a laboratory by a defined test method.
Ash content
Definition
Ash content is the percentage of non-combustible mineral residue left after charcoal fully burns. Lower is better: ash does not produce heat, so a high-ash coal leaves more tray residue, chokes airflow, and can dull a session.
Mulia Charcoal's ash content runs 1.6–2.8% depending on the grade ordered — Premium 2.5–2.8% · Super Premium 2.0–2.5% · Platinum 1.6–2.0% (contractual).
What counts as a "good" ash content is best answered as a graded framework, not a single number — see the three-tier ash grading framework, where Mulia Charcoal's flagship grade sits in the Platinum band.
Fixed carbon
Definition
Fixed carbon is the share of solid combustible carbon that remains after moisture and volatile matter are driven off — the fuel that actually delivers sustained, even heat. Higher is better, and it tracks closely with burn time and heat output.
Mulia Charcoal's fixed carbon is set per grade: Platinum ≥ 82% · Super Premium ≥ 80% · Premium ≥ 75% (contractual).
Moisture content
Definition
Moisture content is the percentage of water held in the charcoal. Lower is better: damp coal is slow to light, can smoke or spit, wastes shipped weight, and is more prone to mold in transit.
Mulia Charcoal's moisture content is ≤ 6% for every grade (contractual).
Volatile matter
Definition
Volatile matter is the portion that vaporizes and burns off as gas when the charcoal is heated, rather than burning as solid carbon. For shisha, lower is better — high volatile matter is associated with more smoke and off-odors that can carry into the session.
Across the 2 independent laboratory reports we hold, Mulia Charcoal's volatile matter is 7.94–10.93% (measured, grade not stated).
Calorific value
Definition
Calorific value is the gross heat released per kilogram when the charcoal is fully combusted, expressed in kcal/kg. Higher means more heat per coal — it underpins how quickly a bowl reaches temperature and how steadily it holds.
Mulia Charcoal's calorific value is set per grade: Platinum ≥ 7,500 kcal/kg · Super Premium ≥ 7,300 kcal/kg · Premium ≥ 7,000 kcal/kg (contractual).
Note
The measured values on this page are the range across 2 independent laboratory reports: Beckjorindo S69863 (2026-06-20) and Carsurin 125856 (2026-07-12). Proximate analysis by ASTM D1762.
2. Observed performance indicators (Tier B)
These describe how the charcoal behaves and looks. They are read under defined conditions, not measured to a laboratory standard.
Burn time
Definition
Burn time is how long a single coal sustains usable heat in a session. It is an observed performance indicator, not a standardized laboratory measurement, so it varies with cube size, heat management, and bowl setup.
Mulia Charcoal's burn time per session is set per grade: Platinum ≥ 2.5 hours · Super Premium ≥ 2 hours · Premium ≥ 2 hours (contractual).
Ash color
Definition
Ash color is the color of the residue left after a coal burns out — a visual indicator of mineral content and how completely the carbon combusted. A light, uniform ash generally signals low mineral content and a clean burn; dark or sooty ash signals the opposite.
3. Reading a Certificate of Analysis
When the Certificate of Analysis for your batch arrives, read it line by line against the parameters above: ash, moisture, and volatile matter should sit at or below their target bounds; fixed carbon and calorific value at or above theirs. A figure outside a target bound is your cue to ask about the batch before shipment.
For what a Certificate of Analysis is and who issues it, see what a Certificate of Analysis contains. For the procedures that produce each figure, see the testing methods behind the values.
4. Don't spec sheets lie? Why trust these numbers?
Note
It's a fair objection: any factory can type "1.8% ash" into a PDF, and a clean lab figure on paper does not guarantee a clean session in your customers' bowls. Experienced buyers are right to distrust an unverified spec sheet.
Two things separate a real number from a marketing one. First, every figure on this page carries its basis in brackets — a range by grade or a value measured by an independent laboratory — not a single flattering headline. A factory gaming its specs quotes one perfect number; an honest one shows its range. Second, these are specs you can confirm without taking our word for it. Ash, moisture, volatile matter, and calorific value are all determined by defined test methods you can have re-run independently, and burn time and ash color are deliberately filed as observed indicators, not lab claims — we tell you which numbers are lab-grade and which are not. The decisive answer to "does the paper match the coal?" is a sample: request one, run your own bowl test, and check the Certificate of Analysis that ships with your batch line-by-line against the figures above. The spec sheet is the claim; the sample and the COA are how you verify it.
Specifications — frequently asked questions
What is a good ash content for shisha charcoal?
What does low ash mean?
What is calorific value (kcal/kg)?
What do the numbers on a COA mean?
Answered on another page: How long does your charcoal burn?