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Common Pseudofossils


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Flint Nodules
Cherty lumps

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Photo courtesy Arco Ardon of Flickr under Creative Commons license
Lumps of flint—a tough, dark form of chert—form in beds of chalk and limestone for poorly understood reasons. They can take a wild variety of shapes, like this French specimen. Inside, they display the typical waxy luster of chert rather than the sandy appearance of concretions.
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