Who decides that a hash is six star, and on what evidence

A star rating is a result that the seller produced, from a test the seller designed, under conditions the seller chose and did not write down. Everything else on this page follows from that sentence.

The scale itself is not a fraud. It refers to something real — how completely a resin melts on a hot surface without leaving residue — and that behaviour genuinely tracks how cleanly the trichome heads were separated from the plant material. The problem is not the idea. The problem is that between the idea and the number on the label there is no method, no independent party and no record.

This page sets out where the scale came from, the five things that separate a rating from a measurement, what the stars still correlate with despite all of it, and what a buyer can ask for instead.

⚠️ Scope. This page describes a commercial designation and what can be verified from documents. It does not describe what a product does to a person, gives no amounts, and does not replace a healthcare professional.

Where the scale actually comes from

It is an English-language invention

The star scale and the phrase that anchors it are Anglophone in origin, from North American concentrate culture, and they travelled outwards from there as loanwords. French and German shops use the English terms untranslated, which is itself a clue: a designation with a legal definition gets translated, because the definition travels with it. One without a definition travels as a sound.

The test behind it

The original observation is a melt test. A small quantity of resin is placed on a hot surface. Material consisting mostly of intact trichome heads liquefies and eventually vaporises, leaving little or nothing behind. Material carrying plant fragments chars and leaves a dark residue, because the plant matter does not melt at all.

Why residue is the informative part

The residue is the fraction that was never resin. That is the whole logic, and it is sound: what remains on the surface is what the separation failed to remove. A scale built on that observation is measuring purity of separation by difference.

How the number of stars got attached

By convention, and gradually. More stars came to mean less residue. Nobody wrote down how much less, at what temperature, on what surface, or judged by whom.

The five things that make a result a measurement

A written method

Temperature, mass of sample, type of surface, duration, ambient conditions. Without them two people running “the same” test are not running the same test. A stated method is what makes a result repeatable by someone who was not there.

A defined observation

What counts as residue, and how much of it separates one grade from the next. A scale needs cut-offs expressed in units, otherwise the boundaries move with whoever is looking.

An independent operator

Somebody with no stake in the answer. This is the point of accredited testing under ISO/IEC 17025: not that the laboratory is clever, but that it is not the seller.

Reproducibility

Two competent operators, working separately from the written method, arriving at the same grade. Until that has been demonstrated, a scale is a habit rather than an instrument.

Traceability to a batch

The result has to attach to a specific production run, identified by number. A grade that describes the product line in general describes nothing that you can hold in your hand.

How many of the five the star scale has

None of them. That is not a rhetorical flourish; go through the list one at a time. There is no published method, no numeric cut-off, no independent operator, no reproducibility study, and no batch number attached to the grade.

The comparison that settles the question

A certificate of analysis

Third-party result, standardised method, batch number, date, laboratory identity, quantified values with a stated limit of quantification. It can be wrong, and when it is wrong there is somebody to hold responsible for it being wrong.

A star rating

First-party result, unspecified method, no batch, no date, no operator, no units. It cannot be wrong, because there is no statement precise enough to be contradicted.

Why the second cannot be corrected

A claim that is not falsifiable is also not correctable. If a seller calls a material six star, there is no test you can run that establishes it was five, because no definition of six exists to fail against. Complaints have no object.

What this means for comparison shopping

Two shops using the same number are not making the same claim, and are not necessarily even describing the same kind of product. Comparing across shops on stars alone compares two private vocabularies.

The compression nobody mentions

The bottom half is never used

Nothing is advertised as one star, or two. In practice the floor is around four, because a seller choosing their own grade has no reason to choose a low one.

What that leaves

Roughly three usable steps out of six, at the top of the range. A six-point scale with three live positions carries about as much information as “fine”, “good” and “best” — which is what it actually means.

Why the top step is special

The highest grade is where the scale stops, so it absorbs everything above it. It is the position with the least information, not the most, because it has no ceiling to be measured against.

The anchoring effect on price

Once the floor rises, the numbers stop describing the material and start describing the price bracket. The grade becomes a label for a tier, applied after the price was decided rather than before.

What the stars still correlate with

Mechanical separation

Ratings cluster at the top for material made by sieving or ice-water separation rather than by pressing whole plant matter. That correlation is real, and it is the reason the scale survives.

A narrow micron band

Material collected from a restricted range of mesh sizes contains a more uniform population of glands and less contamination from other fractions. This shows up in a melt test.

Fresh-frozen input

Material frozen immediately after harvest tends to yield more intact heads, because the glands are brittle and separate cleanly rather than smearing.

Careful drying

Residual moisture spoils a melt test as surely as plant matter does. A high grade implies drying was done properly, whether or not anyone says so.

Why the correlation does not rescue the scale

Because you cannot run the inference backwards. All those things produce a good melt, but the grade on the label was not produced by any of them — it was typed by a person. The correlation holds for the material and not for the claim about it.

What replaces the stars usefully

The separation method, stated plainly

Sieved dry, ice-water separated, or pressed. Three words that tell you more than any grade, because they describe a process rather than a verdict.

The micron range

The mesh sizes used, when the seller knows them. A stated band is a factual claim that can be right or wrong, which already puts it ahead of a star.

The number of passes

First pass from a batch of raw material differs from the third. Sellers who track this will say so, and those who do not, cannot.

The batch certificate

Cannabinoid content, contaminants, solvent residues, batch number. It does not grade the melt, but it covers everything the melt was standing in for and rather more besides.

The seller’s willingness to answer

Ask the three questions above. What you learn from the answers is not only the content of the answers — it is whether this seller knows what they are selling.

Why concentration raises a legal question

The threshold applies to the product as sold

Concentrating resin concentrates everything present in the starting material, including the fraction that is regulated. A raw material comfortably under the limit can produce a concentrate that is not.

How the sum is computed

Total THC is delta-9-THC plus THCA multiplied by 0.877. The factor is a ratio of molecular masses, because the acid form loses a carboxyl group under heat and becomes the neutral form.

Why the acid form counts

Because the material is normally heated before use, and heating converts it. A certificate showing only the delta-9 line has left out the part that will arrive later.

Where this catches people out

A seller quoting the field limit for the crop rather than the measured content of the finished product. Those are different numbers governing different things, and only the second one is about what is in the package.

What the certificate has to show

The batch number

Printed on the packaging, matching the document. Without that match the certificate belongs to some other material.

The date

Analyses age. A document from two years ago describes a batch, correctly, that is no longer the batch in front of you.

The laboratory

Name, and accreditation where it exists. An unattributed table of numbers is a table of numbers.

The full cannabinoid panel

Both THC lines, so the sum can be computed rather than assumed. One line is not enough to work out the figure that the limit applies to.

The contaminant panel

Heavy metals, pesticides, residual solvents, microbiology. Concentration concentrates these too, which is precisely why they matter more here than in a flower.

A parallel that makes the mechanism obvious

Extra virgin olive oil

Defined by EU regulation, with numeric limits on free acidity and peroxide value, verified by laboratory analysis. A producer who uses the term without meeting the limits is breaking a rule with a number in it.

Hotel stars

Set by national bodies, with different criteria in different countries. Loose, but written down and audited by somebody who is not the hotel.

Star-rated hash

Neither. No regulation, no body, no audit, no criteria. It is the only one of the three where the person applying the label and the person benefiting from it are the same person.

What the three have in common

All of them look identical on a shelf. The difference is entirely in what stands behind the label, and none of it is visible at the point of sale.

What a careful seller does with the scale

Uses it and explains it

Some shops publish their own criteria — what they mean by each grade, in their own words. That does not make it a standard, but it makes it a stated claim rather than a bare number.

Puts the process next to it

A grade accompanied by the separation method, the micron band and the pass number is a summary of information given elsewhere. That is a legitimate use of shorthand.

Does not use it as the only description

The failure mode is a product page where the grade is the entire specification. If removing the stars would leave nothing, the stars were not summarising anything.

Answers when asked

The practical test. A seller who can say why this batch is graded as it is has a reason; one who cannot has a habit.

How the scale behaves across markets

In English-language shops

Used most, and most confidently, because the vocabulary is native there. Confidence is not evidence of definition.

In continental European shops

Imported wholesale, often alongside the English word for the top grade. The term arrives without the context that produced it.

Why translation would have helped

Rendering the concept into another language forces somebody to decide what it means. Keeping the English preserves the ambiguity intact, which is convenient.

What this predicts

That the grades drift further apart the more shops use them, since nothing anchors them. This is observable: the same number covers visibly different material in different places.

What the price actually reflects

Input cost

Fresh-frozen material, cold rooms and careful handling cost money before any separation happens. A large part of the price is decided upstream of the grade.

Yield

Higher grades come from narrower fractions, so more of the starting material ends up outside the selection. Less product per kilo means a higher price per gram.

Labour

Sieving, washing, drying and sorting take time, and the difference between careful and hasty work is mostly hours.

The grade itself

Which reflects all three of the above, indirectly and unreliably. Paying attention to the first three makes the fourth redundant.

Where the residue actually comes from

Plant fragments

Leaf and stalk material carried through the separation. It does not melt at any temperature the test uses, so it chars and stays on the surface. This is the source the scale was built to detect.

Waxes and lipids

Plant fats collected alongside the resin. They melt, but they do not vaporise cleanly, and they leave a film that reads as failure even though the separation may have been competent.

Residual moisture

Water left in the material after drying. It spits and darkens the surface, producing an appearance indistinguishable from contamination to anyone watching rather than measuring.

Degraded resin

Material that has oxidised with age or heat. It behaves differently under the test than fresh resin of the same origin, so the same batch can grade lower six months later without anything having been added to it.

Why this matters more than it seems

Four distinct causes produce one observation. Even taken purely as an observation, before any question of grading, the melt test cannot say which of the four it has found — and only one of them is the thing the scale claims to measure.

The property the scale optimises for

The test assumes a use

A hot surface, and a user watching what happens on it. The whole scale is built around that scenario, because that is the setting it came from.

Most buyers are not in that setting

A resin bought in the European market is more often crumbled, warmed gently or simply kept. The melt test describes a behaviour that many buyers will never observe and were not shopping for.

What it means to grade on an unused property

The number ranks material by how it performs in a situation that may not arise. That is not the same as ranking it badly; it is ranking it against the wrong question.

What the buyer usually wants instead

Content, contaminants, consistency between orders, and a seller who describes the process. All four are documented, and none of them appears in the grade.

Why the grades only ever drift upwards

The person grading is the person selling

There is no cost to choosing the higher number and an obvious benefit. Any scale with that structure moves in one direction.

Nothing pulls it back down

Correction requires a definition to appeal to. Since none exists, an inflated grade cannot be challenged, only matched by the next shop.

The ratchet

Once a competitor grades a comparable product higher, matching it becomes the neutral move rather than the aggressive one. The floor rises again, the range compresses further, and no individual shop ever has to decide to inflate anything — each one is only keeping pace with the shelf next to it.

What that predicts over time

That the numbers keep climbing while the material stays where it was, until the top of the scale means what the middle used to mean. This is the ordinary fate of any self-applied grade.

A short glossary

Melt test

Heating a small sample on a surface and observing how completely it liquefies and how much residue remains. Informative as an observation, not standardised as a method.

Residue

What is left on the surface after heating. It is the fraction that was not resin, which is why it is the informative part.

Trichome head

The gland at the tip of the stalk, where the resin is produced and held. Separation processes exist to collect these and leave the rest.

Micron

One thousandth of a millimetre, the unit used for mesh sizes. A stated range describes what was collected and what was excluded.

Full spectrum

A product retaining the accompanying plant compounds, including a regulated fraction. It is a description of composition, not of quality.

Batch

One production run. Every verifiable claim attaches to a batch, and a claim that does not attach to one cannot be checked.

Accreditation

Formal recognition that a laboratory is competent for a named method, granted by a national body. It is what makes an outside result worth more than an inside one.

The five checks that apply to any product

The batch certificate

Request it with the number printed on the packaging. A general document for the product line does not cover this batch, and those differences are exactly what it should record.

Total THC

Delta-9-THC plus THCA multiplied by 0.877, because THCA becomes THC under heat and the limit applies to the sum, not to either value alone.

Price per gram

A division, not an opinion. The only figure that makes two offers comparable, whatever grade each one claims.

The claims

Without an authorisation number in the EU Register these are assertions, not data — and for cannabidiol that register contains no authorised entry to this day.

The seller’s details

Company name, address and contact. Without them there is also no counterparty to turn to if something turns out to be wrong.

How this connects to the rest

With the micron ranges

The sieve band explains what the melt test observes. It is the underlying fact that the grade is gesturing at.

With reading a texture

Both are tactile or visual checks with no document behind them. Both are useful as diagnosis and useless as classification.

With the separation methods

Dry sieving and ice-water separation produce different material from the same plant. The grade does not record which was used, so it has to be asked separately.

With the certificate

Everything ends there. The grade appears on no analysis report, and the analysis report answers the questions the grade cannot.

What this is for in practice

Facing a product page

Look for what sits next to the grade. Method, micron band and pass number turn shorthand into a summary of real information; their absence leaves a number describing itself.

Facing two offers with the same grade

Read the match as coincidence. Compare price per gram and what each seller will state about the process, since the grades came from two different people using two private scales, neither of them written down anywhere.

If you simply want to understand

That the scale points at something real and reports it in a form that cannot be checked. Both halves of that sentence matter.

What this page publishes

Processes, verifiable documents and arithmetic. No promises of effect — for that, the EU Register contains no authorised entry.

Frequently asked questions

What does a six star rating mean? Nothing defined. It is the top of a scale that no body maintains, applied by the seller, with no method behind it. It usually indicates the most expensive grade that shop offers.

Is the star scale regulated anywhere? No. There is no standards body, no published criteria and no audit for it in any market. The comparison with extra virgin olive oil, which is defined numerically in EU law, shows what regulation of a designation actually looks like.

Does a melt test tell you anything at all? Yes, as an observation. Residue is material that was never resin, so less residue does indicate cleaner separation. What it does not give you is a grade, because there is no agreed method or cut-off.

Why do sellers use it if it means nothing? Because it is compact, familiar, and flattering. It also does correlate with real production differences, which makes it feel informative even where it is not verifiable.

Can I trust a shop that publishes its own criteria? It is better than one that does not, since a written criterion is a stated claim. It still is not a standard, because the shop is grading its own work.

What should I ask instead? Separation method, micron range, number of passes, and the batch certificate. Four questions, all of which have factual answers.

Does a higher grade mean more CBD? Not reliably. Cleaner separation tends to concentrate the resin fraction, but the actual content is on the certificate and nowhere else.

Why is the bottom of the scale never used? Because the seller chooses the grade. A scale where the person applying it also benefits from it drifts upwards, which is why the usable range is about three positions rather than six.

Is full melt the same as full spectrum? No, and the similarity of the phrases causes real confusion. One is an informal claim about melting behaviour; the other describes composition and implies the presence of a regulated fraction.

Does the grade appear on a certificate of analysis? Never. A certificate reports quantified values from a defined method, and the grade is neither quantified nor defined.

What we check and what we do not

We check what can be checked from documents: official registers, declared contents, certificates of analysis, divisions. We do not test products, do not produce rankings and do not claim any effect.

On this subject the boundary is unusually clear, because the designation itself sits entirely outside what any document records. There is no register to consult and no report on which it appears.

What remains within reach is the arithmetic, the certificate, and four questions that a seller can answer or cannot. That is a smaller thing than a grade appears to offer, and considerably more solid than what it actually delivers.