chert

About 0.85 uses per million words.

Meaning

1. noun Massive, usually dull-colored and opaque, quartzite, hornstone, impure chalcedony, or other flint-like mineral.
2. noun A flint-like tool made from chert.

Similar words

spilite quartz radiolarian metachert chertification quartzine chalcedonyx chalcedony calcedony phthanite

Often followed by

and is in nodules flakes or of from beds

Word family

chertier chertiest cherts cherty