… than natural sands); quartzite, whether or not roughly trimmed or merely cut, by sawing or otherwise, into blocks …
Explanatory notes
… than natural sands); quartzite, whether or not roughly trimmed or merely cut, by sawing or otherwise, into blocks … allowed in Note 1 to this Chapter; for this purpose, heat treatment designed solely to facilitate crushing is regarded … intended to be used for technical purposes, e.g., as piezo‑electric quartz or for the manufacture of parts of tools. …