Materials and Clay Index

Every row is a verbatim sentence read from the named source's own page through our fetch service on the date shown, hash-pinned to the stored read (the sha of the page's visible text; the raw page is mirrored to R2).

2 of the 23 named sources that could be read published a usable figure; 21 published none and are recorded as not published, never filled in; 1 could not be read (blocked, dead or unreachable) and count nowhere.

The headline figures (median, minimum, maximum, quartiles) are over ONE figure per source in USD (a source's median where its page yielded several accepted sentences), so N counts sources, never sentences; 44 candidate sentence(s) were refused by a reviewer with the reason recorded.

The fuller derivation this dataset is chartered to grow into (not yet what the figures above are; they are each source's own published figure as read): one row per material and per named clay body: what it is and what it does (function in a body or a glaze), and every price a seller publishes for it, normalised to a unit - per kilo, per pound, per 12.5kg or 25lb bag - across US and UK sellers; the derived figures are the median, low and high price per material, the US/UK spread on the same material once currency and unit are normalised, the count of sellers publishing a price versus quote-only, and repriced-since the previous read.

No one publishes that: each seller publishes its own list and the reference sites publish chemistry with no prices.

44 candidate sentences on these pages were refused by a reviewer; each refusal and its reason is recorded in the review ledger.