CBD moon rock: three layers and a percentage to check

A moon rock (also spelled "moonrock") is an assembled product, and the name does not refer to a strain. A dried hemp bud is coated with a concentrated CBD extract and then rolled in kief. The result, a grey, powdery ball resembling a lunar pebble, gives the product its name.

French shops sell the kief layer as "pollen", a confusing label. The powder has nothing to do with the botanical pollen of male flowers: it comes from sifting trichomes, the resin glands covering the flower. Professionals call it dry sift or kief. How it is made and graded is covered in our guide to CBD pollen.

The middle layer may be a distillate or a dissolved isolate, and this is the layer that drives the percentage up. As our article on CBD isolate explains, an isolate normally contains 99% CBD or more.

The percentage of a moon rock is a weighted average: add the milligrams of CBD from each layer, then divide by the total mass. For the example, take three plausible values: a flower at 10% CBD, an extract at 85% and kief at 25%.

With 1 g of flower, 0.3 g of extract and 0.2 g of kief, you obtain 1.5 g of product containing 405 mg of CBD, or 27%. That is already close to three times the level of the starting flower.

Reaching 60% with the same flower and kief would take about 2.3 g of extract per gram of flower, so the coating would weigh more than twice the bud beneath it. This gives a simple rule: above 50% CBD, a moon rock is mostly extract. That is no flaw in itself. It does change the nature of the product, and with it the questions to ask about the origin and purity of that extract.

The reasoning works in reverse too. A moon rock labelled at 10% has either a very thin coating or more in common with a flower than with a moon rock.

Not always, as public data show. In 2017 a study in JAMA had 84 CBD extracts sold online in the United States tested, from 31 brands. Allowing a 10% tolerance, only 30.95% carried an accurate label. Less CBD than stated was found in 42.85% and more in 26.19%, and THC was detected in 18 of them.

The same holds in France. The ANSM, the French medicines agency, cites in a warning dated 19 June 2025 a 2023 survey by the addiction-monitoring centres of Lyon, Paris and Montpellier. It found a CBD content differing from the label in 8 products out of 10.

A moon rock combines three materials of separate origin, each with its own margin of error, so these gaps can add up. Only a certificate of analysis for the batch on sale settles the question. The lines to check are shown in our guide to reading a certificate of analysis, and our laboratory page lists the catalogue products.

Moon rocks come under the rules for hemp flowers. The Conseil d'État annulled on 29 December 2022 the ban on selling raw flowers and leaves. The order of 30 December 2021 sets the ceiling at 0.3% Δ⁹-THC for the varieties, for "hemp extracts" and for "the products that incorporate them".

For a moon rock, that last point counts. The coating is itself a hemp extract and must meet the threshold. A full-spectrum extract concentrates THC as well as CBD, and above 0.3% it puts the product outside the law even when the starting flower was compliant. Our article on the legal THC limit explains how it is measured.

Since a moon rock is not a food, the French Agriculture Ministry notice of 20 May 2026, which states that foods containing CBD are not authorised, does not cover it. Driving rules still apply, and THC detected at the wheel is an offence whatever the dose.

With a moon rock, the larger risk lies in what the coating can hide. The ANSM reports poisonings linked to products sold as CBD that contained HHC, H4CBD or MDMB-PINACA, all classified as narcotics. A layer of extract and powder easily carries such additives, and they are invisible to the eye. How H4CBD found its way into products sold as CBD is explained in our article on H4CBD.

Check four points on the certificate before buying:

1. The batch number is the same as on the pouch.
2. Δ⁹-THC is at or below 0.3%.
3. The measured CBD percentage is consistent with the calculation, with extract dominating above 50%.
4. The lab searched for HHC, H4CBD and synthetic cannabinoids and found none.

An effect resembling that of cannabis is another warning sign, since CBD has no psychoactive effect. Our Moonrock is listed with our other CBD flowers.