Name:  Chalk

Geologic Name:  Selma Chalk

Reference:  Stephenson, L.W., Cretaceous deposits of the Easter Gulf
Region: U.S. Geol. Survey Prof. Paper 81, p. 15-17, 21, 1914.

Microscopic characters:  The rock consists of numerous foraminifera embedded 
in a fine mosaic of calcite and chalcedonic quartz.  There are a few large grains
of quartz, slender flakes of muscovite, and grains of magnetite altering to
hematite.  Ferric oxide, leucoxene and a brownish, cloudy substance obscure
portions of the slide.