Derby-Doerun Dolomite

Derby-Doerun Dolomite Stratigraphic range: Upper Cambrian
Type	Formation
Unit of	Elvins Group
Underlies	Potosi Dolomite
Overlies	Davis Formation
Lithology
Primary	Dolomite
Location
Region	St. Francois County, Missouri
Country	United States

The Derby-Doerun Dolomite is a Cambrian geologic formation exposed in southeast Missouri. Originally the Derby and Doerun were originally considered separate formations, but now considered a single unit. The combined name is from the Derby Mine and the Doe Run Lead Company of the Old Lead Belt.

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