What rock type would be made mostly from particles 1/256 millimetres and has lots of thin flat laminae and a reddish colour?

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Quizplus · Accepted Answer

Ferruginous shale is a fine-grained rock composed of silt-sized particles, like those that are 1/256 millimeters in size. This rock contains thin, flat layers (laminae) which are characteristic of shales, and a reddish color may indicate the presence of iron oxide minerals. Carbonaceous mudstone is also a fine-grained rock, but it is composed mainly of clay minerals rather than silt-sized particles. Calcareous siltstone contains more calcium carbonate and may have a more gray or tan color. Wilma Flintstone is not a rock type, but a cartoon character.

What Rock Type Would Be Made Mostly from Particles 1/256