red clay

geology

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July 13, 2026

Quick Summary

Red clay is a type of clay that gets its reddish color from iron oxide. In geology, clay refers to soil particles smaller than 0.005 millimeters, or rocks composed of these particles. These materials are plastic when wet and firm when dry, often forming from the weathering of rocks.12

Clay minerals are fine-grained fragments, primarily composed of hydrous-layer silicates of aluminum, magnesium, and iron. Their chemical formulas, like kaolinite (2SiO₂·Al₂O₃·2H₂O), are key to classifying them into various groups.3

A specific type of red clay is found in the deep ocean, accumulating slowly on the ocean floor. This abyssal deposit consists of insoluble materials from volcanic and cosmic dust, mixed with manganese oxide nodules, zeolite crystals, and organic debris.1

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mining
The seafloor
An estimated 10¹⁶ tons of red clay covers about 104 million square km (40 million square miles) of the ocean floor. Although compositional analyses are not particularly exciting, red clay may possess some value as a raw material in the clay products industries, or it may serve as a source…
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An estimated 10¹⁶ tons of red clay covers about 104 million square km (40 million square miles) of the ocean floor. Although compositional analyses are not particularly exciting, red clay may possess some value as a raw material in the clay products industries, or it may serve as a source…
Read More

Pacific Ocean
Bottom deposits
…where the characteristic deposit is red clay. Red clay, which covers no less than half of the Pacific floor, is believed to be formed of colloidal (extremely finely divided) clays derived essentially from the land.
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…where the characteristic deposit is red clay. Red clay, which covers no less than half of the Pacific floor, is believed to be formed of colloidal (extremely finely divided) clays derived essentially from the land.
Read More