Oolitic Limestone
“Stone made of tiny pearls”
Oolitic limestone is composed of tiny, rounded grains called ooids — small spheres of calcium carbonate that form as layers of mineral precipitate around a nucleus like a sand grain in warm, shallow, wave-agitated seas. Under magnification, each ooid reveals concentric rings like a miniature pearl.
calcite ooids, calcite cement, fossil fragments, quartz
Bath (England), Indiana (USA), Bahamas (modern formation), Jura Mountains (France/Switzerland)
3-4
The famous honey-colored buildings of Bath, England — including the Royal Crescent — are built from oolitic limestone quarried locally, giving the entire city a warm golden glow.
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What conditions are required for ooids to form in modern marine environments?
Related Specimens
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