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Quarried at Aquia Creek in Stafford County, Virginia, the stone was valuable for its ease of shaping and the quarry's proximity to the tidewater portion of the Potomac River, 45 miles (72 km) south of Washington. The sandstone was the principal material used in such significant buildings as the White House and the early stages of the U.S ...
The sandstone was quarried as dimension stone, ton stone, and rubble stone, with dimension stone the most marketable and costly. Blocks of dimension stone typically measured 8 by 4 by 2 ft (2.44 by 1.22 by 0.61 m). [50] The byproduct of removing the dimension stone was rubble stone, which was either sold cheaply or discarded entirely. [51]
numerous types, some without trade names, from the Karoo Supergroup in many quarries near Graaff-Reinet, Cradock, Queenstown, Aliwal North, Burgersdorp and Sterkstroom Těšínský sandstone quarry (Goulda Sandstone)
Today nearly all these old quarries are flooded and a few are owned by camping resorts, rod and gun clubs or conservation clubs and used for recreational activities. Even though building stone was a relatively small percent of quarry output, the Medina sandstone legacy can be best seen today in the magnificent buildings built from this stone.
Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains, cemented together by another mineral. Sandstones comprise about 20–25% of all sedimentary rocks.
The sequence is made up of 22 m thick cycles, each with a basal erosion surface followed by dark grey shales with desiccation cracks, planar cross-bedded sandstones with wave rippled tops, overlain by trough cross-bedded micaceous sandstones. These cycles are thought to represent repeated progradation of deltas into a lake.
Examples can be seen in the Mississippi River Gorge and at Minnehaha Falls in Minneapolis, the bluffs from downtown to Mounds Park in Saint Paul, and Minneopa Falls near Mankato. In Illinois, Castle Rock is a large bluff of St. Peter Sandstone, and Starved Rock State Park and Matthiessen State Park feature numerous outcroppings and canyons.
As sandstones, these are known as lithic sandstones. Arc sands plot along the F and L line, with sometimes significant Q components. Clustering near the F pole indicates a dissected arc, and clustering near the L pole indicates an undissected, or new arc. As sandstones, these are known as arkoses and/or lithic sandstones.