dull-lustered

Updated: May 22, 2025

Flint is a form of quartz, dull-lustered, usually gray or blackish in color, and opaque except on thinnest edges, where it is translucent. Over much of the northern states there is spread an unstratified stony clay called the drift. It often rests on sound rocks. It contains grains of sand, pebbles, and bowlders composed of many different minerals and rocks that the country rock cannot furnish.

William Harmon Norton - The Elements of Geology