Chert

Dull, flinty grey, like the inside of a river-worn rock.

#848182

Chert is a neutral grey.

It can be described as neutral, medium and colorless.

Set in black, because black reads best on it.

Chert

Chert is a hard, fine-grained sedimentary rock composed of microcrystalline or cryptocrystalline quartz, the mineral form of silicon dioxide (SiO2). Chert is characteristically of biological origin, but may also occur inorganically as a chemical precipitate or a diagenetic replacement, as in petrified wood. Where chert occurs in chalk or marl, it is usually called flint.

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chert

Noun

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

Wiktionary

Its neighbors.

Trolley Grey, #818181 Captain Nemo, #828080 Pound Sterling, #818081 Squant, #828383 Storm Cloud, #808283 Sharkskin, #808184 Lingering Storm, #858381 Lunar Federation, #868381 Lunar Outpost, #828287 Grey, #808080 Mt. Rushmore, #7f8181 Mission Control, #818387

Chert

#848182

Chert

Chert

chert

Its neighbors.

Its complements.

As a ramp.