Dover Chert

2010 by the Center For Social Research, Parkland College

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The texture is medium.

Luster is waxy.

Dover chert can be described as a light brown to dark brown matrix with varying dark to light linear to swirling or mottled patterns.

Note the abundance of fenestrate bryozoa fossils (cf. Parish 2009b:46). They are of white ranging to light blue coloration and of a distinct crystalline expression. There many linear or bar-shaped, non-crystalline fossils that may be sponge spicules.

There is occasional druse and a few oolites.

Dover Chert was not typically heat treated.

The illustrated specimens were collected from the type locality in Stewart County, Tennessee. They were generously provided by Billy Guedon of the U.S. National Park Service, Russell Cave National Monument, Alabama.

The Dover quarries of Stewart County, Tennessee are the type locality for Dover Chert. Macroscopically similar material is widely exposed throughout the lower Tennessee and Cumberland River valleys where it is recovered primarily as either residuum or streambed alluvium (Nance 2000:84-85). It has also been reported from southern Illinois ((Meyers 1970).

At the Dover locality, Parish recognizes two color variants: dark matrix and light matrix (light brown, caramel, or white). The illustrated objects fall into the light matrix category. The presence of soil adhering to the cortex supports his observation that the lighter colored variants are recovered from "...within the soil matrix." (Parish 2009b:48).

After decades of speculation (Stelle 1984:155-156), recent fieldwork by Parish notes that the main chert bearing formations in Stewart County are the St. Louis, Warsaw, and Fort Payne limestones of the Mississippian System. Dover is found on top of the Warsaw and at the base of the St. Louis and is concluded to be residuum of the St. Louis Formation (Parish 2009b:121, 126, 135).

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