Paleogene and Neogene (also known as Tertiary Age, 65 to 1.6 million years ago) rocks and sediments were deposited after the dinosaurs became extinct, during the time called the Cenozoic Era. These strata are shown in green and yellow entirely within the Jackson Purchase Region (unfortunately, the Cretaceous is also shown in green). The yellow areas inside the Jackson Purchase contain Quaternary and Tertiary sediments, whereas the yellow areas outside the Jackson Purchase are Quaternary only.
Tertiary sediments in Kentucky include numerous deposits of ball clay, which can be used for ceramics and enameling. Kentucky is the second largest producer of ball clay in the United States. A low grade of coal called lignite is also is also found in some areas of the Jackson Purchase, but the deposits are not currently economic to mine.
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