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CAROLINA GEOLOGICAL SOCIETY
Guidebook for 1992 Annual Meeting
Pages 87-88
SILVER BLUFF: A VERY CELEBRATED PLACE
W.C. Fallaw
Department of Geology
Furman University
Greenville, South Carolina
David S. Snipes
Department of Earth Sciences
Clemson University
Clemson, South Carolina
Van Price
Westinghouse Savannah River Company
Aiken, South Carolina
Silver Bluff, located in the Coastal Plain on the Savannah
River in Aiken County, South Carolina (Jackson, SC-GA
7 ½’ quadrangle, longitude 81 °51;08” W, latitude 33 o 18’
40”N) is the highest point on the South Carolina bank of the
Savannah for many miles, rising approximately 30 ft above
water level on the cut bank of a meander. Exposed in the
bluff is a section of yellowish-gray clay and bluish-gray, lignitic
lay overlain by mottled, yellow and reddish, poorly
sorted, pebbly sand and clay. We sent samples of lignitic clay
from near the base of the section to two commercial palynological
laboratories. By one the material was dated as Cretaceous
() from one poorly preserved specimen, and by the
other it was dated as Pleistocene() from numerous specimens.
The sediments are probably terrace deposits (Newell
and others, Fig. 9).
According to some (Stokes, 1951, p. 20; Faust, 1982, p.
69), DeSoto’s expedition found a thriving Indian settlement
at Silver Bluff in 1540. The name of the locality derives from
two possible sources. One idea is that it came from a metallic
sheen on the outcrop caused by muscovite (Faust, 1982 p.
69). There is also a story that Spaniards operated a silver
mine there [Bartram, 1791 (Harper, ed., 1958, p. 315)]. They
may have actually been mining, for the manufacture of gunpowder,
concretions of iron sulfide which occur in the lignitic
clay. According to the story, having mined down to
water level, they decided to dig a channel through the neck of
the meander loop and divert the Savannah. On the Jackson
quadrangle map based on aerial photographs taken in 1963, a
meander cutoff named Spanish Cut appears to have been
widened and straightened over a distance of almost 400 ft.,
approximately 1000 ft short of the goal.
William Bartram passed through Silver Bluff, “a very
celebrated place” [Bartram, 1791 (Harper, ed., 1958, p.
199)], several times in the latter part of the eighteenth century,
the locality being on a well-traveled trading path from
the coast to the Indian settlements to the west. In his famous
book (1791), he described in detail a Silver Bluff stratigraphic
section containing belemnites. Belemnites indicate a
Cretaceous age in the Carolinas, but the nearest occurrence
of Cretaceous marine megafossils known to the authors in
33.5 mi to the southeast near Allendale, South Carolina,
where they were found in a well core. Bartram published his
book many years after his expeditions through the area, and
he apparently confused his notes from the Silver Bluff section
with his description of outcrops on the Cape Fear River
in North Carolina, approximately 225 mi to the northeast,
where Cretaceous sediments of the Black Creek and Peedee
formations are exposed. Many of the same words and
phrases in Bartram’s description of Silver Bluff reappear
identically in his accurate account of the North Carolina Cretaceous
outcrops.
In 1831 Silver Bluff became the site of the plantation of
James Hammond, a leading southern intellectual, governor
of South Carolina from 1842 to 1844, and U.S. senator fro
1857 to 1860 (Faust, 1982). Hammond, interested in increasing
the productivity of his land, decided to experiment with
marl. This had been recommended by Edmund Ruffin, a
plantation owner and member of the Virginia aristocracy
(Ruffin, 1843, p. xvii) who promoted application of limestone
to the exhausted soils of the southeast. Hammond,
using slave labor, barged limestone from Shell Bluff, on the
Georgia side of the Savannah, upstream to Silver Bluff,
approximately 11 mi by the present course of the river, to
apply to his fields where shell fragments can still be seen.
The famous outcrop at Shell Bluff has been visited by many
geologists, including Charles Lyell (Lyell, 1845, p. 158).
As governor, Hammond was instrumental in getting
Ruffin to come to South Carolina to find limestone and
encourage its use, and the two agricultural experimenters
became close friends, Ruffin being a frequent visitor to Silver
Bluff (Faust, 1982, p. 114 – 116). Ruffin was such an
enthusiast that a newspaper stated “During his late exploration
of soil through South Carolina, it was remarked of him,
that he was so full of calcareous manures, that if you poured
any sort of acid, acetic, or nitric, on his head he would effervesce,
and indicate the presence of lime” (Mitchell, 1981, p.
87