(Chesterfield County). Sugarloaf Mountain is an erosional remnant located in the Sand Hills State Forest within the upper coastal plain of South Carolina. It lies 513 feet above sea level and 100 feet above the surrounding terrain. From this position and elevation, Sugarloaf offers a wide view of the surrounding landscape. Sugarloaf Mountain is made up of sands, clays, and a sandstone that is capped in places by an ironstone that formed as iron-rich water percolated through the sands, forming a hard, almost impermeable layer. Sugarloaf is one of the few sites where abundant ironstone is found in the Sandhills.
The sand dunes and clays that make up Sugarloaf Mountain were originally rocks of the various high mountain ranges that formed beginning in the Ordovician period and continuing during the Devonian and Permian periods and then wore away. These mountains were located to the north and west of the Sandhills. They were made of rocks such as granite, gneiss, and schist. The minerals found in these rocks included feldspar and mica that chemically weathered into clay, and quartz that physically weathered into sand. Over millions of years these clays and sands were, in turn, carried and deposited by rivers to form unconsolidated sediments, clay deposits, and sandstone that are clearly visible at the surface at Sugarloaf Mountain.
During the Eocene to Miocene epochs, the sea rose to the level of the modern Sandhills, running as an embayment up the river valleys including the Congaree and the Wateree. Sugarloaf Mountain at that time would have formed part of a beach and dune system at the back of the coastline. Over millions of years the ocean has retreated to its present location at the coast.
Kovacik, Charles F., and John J. Winberry. South Carolina: The Making of a Landscape. 1987. Reprint, Columbia: University of South Carolina Press, 1989.
Murphy, Carolyn H. Carolina Rocks! The Geology of South Carolina. Orangeburg, S.C.: Sandlapper, 1995.