Flint from the Mississippian of Tennessee, USA. (~6.4 centimeters across at its widest)
<p>Flint (= chert) is a cryptocrystalline-textured, quartzose sedimentary rock.  It can have a biogenic or chemical origin.
</p><p>Stratigraphy: attributed to the Ft. Payne Formation, Osagean Stage, upper Lower Mississippian
</p>
Locality: undisclosed site in Tennessee, USA
James St. John
CC BY 2.0
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