sedimentary
Coquina
Bioclastic Limestone
AI-generated identification · may be incorrectMohs hardness of 3, pale yellowish-brown color, dull luster, composed of poorly cemented shell fragments, specific gravity around 2.4-2.7.
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Physical properties
Mohs hardness of 3, pale yellowish-brown color, dull luster, composed of poorly cemented shell fragments, specific gravity around 2.4-2.7.
Formation & geological history
Formed in high-energy marine environments where waves accumulate and cement broken shell fragments together.
Uses & applications
Historically used as a local building stone, particularly in coastal fortifications and historic structures.
Geological facts
Famous for being used to construct the Castillo de San Marcos in St. Augustine, Florida.
Field identification & locations
Easily identified by its rough, porous texture resembling a collection of tiny visible shells and fossils glued together.
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