CLAIBORNE GROUP. 29 
TALLAHATTA BUHRSTONE. 
The Tallahatta buhrstone, called the siliceous Claiborne by Hilgard, outcrops in a belt of 
territory between the Wilcox and the Lisbon beds or calcareous Claiborne. This belt 
varies in width from 10 miles in northeastern Clarke County to about 30 miles in Holmes, 
Carroll, and Montgomery counties. 
In lithologic character the Tallahatta buhrstone stands out in sharp contrast to the soft, 
unconsolidated sands, clays, and lignites of the Wilcox, and likewise to the more marine- 
deposits of calcareous clays and fossiliferous marls which were laid down immediately 
after the deposition of the buhrstone. The principal rocks of this formation consist of the 
following: 
1. Aluminous sandstone of a prevailing gray to white color and often containing a large 
amount of oxide of iron. More or less fossils, principally casts, have been found in this 
rock in both Mississippi and Alabama. 
2. Next in order of abundance is the siliceous and aluminous clay stone. This rock is 
found in numerous places near the Alabama border in Clarke and Lauderdale counties, but 
north of this the harder sandstones are the prevailing materials. 
3. Quartzitic sandstone or " Feldsen mur." This is the rock which has given the name to 
the whole series. It is an exceedingly hard sandstone which, by metamorphism, has lost 
much of its original sandy character. Some of the specimens collected show the sandstone 
in the process of change from the coarse-grained sand to the hard quartzite. The quartzite 
is usually found in layers ranging from 2 to 3 feet thick. When long exposed to eroding 
agents it is found strewn along the hillsides in large, flat bowlders. Smith « considers the 
quartzite to be the basal member of the Tallahatta buhrstone formation. This is overlain 
by aluminous clay stone which is flecked with small fragments of clay or "gallstones." 
This clay rock is very light gray to white in color, containing two sets of joints approxi- 
mately at right angles to each other. In places, as at Basic, in northern Clarke County, 
these joints have been filled with sand and other materials forming small dikes, and the 
whole cemented together with iron oxide. The intruded material is more resistant than 
the indurated clay stone and gives rise to unequal weathering. 
4. Greensand and marls. These are found in less abundance than any of the other 
materials. However, more or less greensand grains occur throughout the siliceous sand- 
stone of the formation. 
An interesting section at Vaiden is given by Hilgard : & 
. In the middle of the cut the coarse, glauconitic, dark orange-colored, ferruginous sandstone forms a 
pretty uniform stratum about 3 feet thick; it is in this that the fossils are most abundant. These are 
preserved as impressions and nuclei only. Underlying this rock and in the cut adjoining northward 
alternating with it there occurs a stiff amorphous clay with sharp sand and some greensand grains, 
also of deep orange tint and exhibiting traces of fossils. 
On the south side of Kirkwood Ferry, about sec. 11, T. 16 N., R. 5 E., is a bluff about 70 
feet high showing the Tallahatta buhrstone, of which Hilgard c gives the following section: 
Section of Tertiary strata at Kirkwood Ferry. 
Feet. 
6. White siliceous sandstone; nonfossiliferous 1 
5. Yellow sand, grains rounded; no fossils (orange sand) 3 
4. Dark orange-colored glauconitic sandstone; fossils as at Vaiden 2 
3 Ferruginous sand, somewhat glauconitic, with few fossils 20 
2. Gray laminated clay \ 
1. Yellow sand, without fossils 20 
No accurate measurement of the thickness of the Tallahatta buhrstone has been made in 
Mississippi. The city waterworks at Kosciusko struck a bed of fossiliferous marl at a 
depth of 65 feet. This marl bed is immediately overlain by a stratum of hard "flint rock" 
34 inches thick, and is underlain by a stratum of softer rock. 
a Coastal Plain of Alabama, p. 140. 
& Geology and Agriculture of Mississippi, 1860, p. 121. 
eOp. cit., p. 122. 
