Verification
A score is only as good as the data underneath it
Rather than average our uncertainty away, we publish it. Every score carries the tier of its weakest material input.
Corroborated by a third party
Evidence required
- Mill or foundry certificate naming the material and grade
- Weighbridge or packing-line record for mass
- Independent lab report where composition is contested
Review cycle
Re-checked every 12 months or on any specification change.
Declared by the maker, spot-checked by us
Evidence required
- Signed input declaration per SKU
- Photographic evidence of packaging as shipped
- Sampling: we weigh a random unit from each batch
Review cycle
Escalates to verified once documentary evidence is filed.
Modelled from category defaults
Evidence required
- Category-median material factors
- Packaging inferred from the shipped configuration
- Distance derived from the stated origin
Review cycle
Flagged as provisional everywhere it is displayed until primary data arrives.
The weakest-link rule
A product's displayed tier is the lowest tier among its material, packaging and logistics inputs. A verified material with estimated packaging yields an estimated score. This is intentionally conservative: it prevents a single well-documented input from lending credibility to the rest.
When we cannot corroborate a claim
The claim is dropped and the input reverts to a category default. We do not display unverifiable supplier claims as fact, and we do not delist a maker for lacking paperwork — the score simply carries a lower tier until the evidence exists.
Reporting an error
Send the product slug and the disputed input via contact. Confirmed corrections trigger a re-score and appear in the version history.