The Ridgeley sandstone is a sandstone

Sandstone

Sandstone is a sedimentary rock composed mainly of sand-sized minerals or rock grains.Most sandstone is composed of quartz and/or feldspar because these are the most common minerals in the Earth's crust. Like sand, sandstone may be any colour, but the most common colours are tan, brown, yellow,...

 or quartzite

Quartzite

Quartzite is a hard metamorphic rock which was originally sandstone. Sandstone is converted into quartzite through heating and pressure usually related to tectonic compression within orogenic belts. Pure quartzite is usually white to gray, though quartzites often occur in various shades of pink...

 of Devonian

Devonian

The Devonian is a geologic period and system of the Paleozoic Era spanning from the end of the Silurian Period, about 416.0 ± 2.8 Mya , to the beginning of the Carboniferous Period, about 359.2 ± 2.5 Mya...

 age found in the Appalachian Mountains

Appalachian Mountains

The Appalachian Mountains #Whether the stressed vowel is or ,#Whether the "ch" is pronounced as a fricative or an affricate , and#Whether the final vowel is the monophthong or the diphthong .), often called the Appalachians, are a system of mountains in eastern North America. The Appalachians...

 of Pennsylvania

Pennsylvania

The Commonwealth of Pennsylvania is a U.S. state that is located in the Northeastern and Mid-Atlantic regions of the United States. The state borders Delaware and Maryland to the south, West Virginia to the southwest, Ohio to the west, New York and Ontario, Canada, to the north, and New Jersey to...

, Maryland

Maryland

Maryland is a U.S. state located in the Mid Atlantic region of the United States, bordering Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware to its east...

, West Virginia

West Virginia

West Virginia is a state in the Appalachian and Southeastern regions of the United States, bordered by Virginia to the southeast, Kentucky to the southwest, Ohio to the northwest, Pennsylvania to the northeast and Maryland to the east...

, and Virginia

Virginia

The Commonwealth of Virginia , is a U.S. state on the Atlantic Coast of the Southern United States. Virginia is nicknamed the "Old Dominion" and sometimes the "Mother of Presidents" after the eight U.S. presidents born there...

, USA

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

. The Ridgeley is fine-grained, siliceous, calcareous in its lower strata

Stratum

In geology and related fields, a stratum is a layer of sedimentary rock or soil with internally consistent characteristics that distinguish it from other layers...

, sometimes fossiliferous, and sometimes locally pebbly or conglomeritic. Varying in thickness from 12 to 500 feet (4–150 m), this rock slowly erodes into white quartz

Quartz

Quartz is the second-most-abundant mineral in the Earth's continental crust, after feldspar. It is made up of a continuous framework of SiO4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall formula SiO2. There are many different varieties of quartz,...

 sand that often washes or blows away, but sometimes accumulates at large outcrops. When freshly broken, the rock is white, but outcrop surfaces are often stained yellowish by iron oxide

Iron oxide

Iron oxides are chemical compounds composed of iron and oxygen. All together, there are sixteen known iron oxides and oxyhydroxides.Iron oxides and oxide-hydroxides are widespread in nature, play an important role in many geological and biological processes, and are widely utilized by humans, e.g.,...

s.
The Ridgeley Sandstone was described and named in 1913 from an outcrop in Ridgeley, West Virginia

Ridgeley, West Virginia

Ridgeley is a town in Mineral County, West Virginia, United States, and part of the Cumberland Metropolitan Statistical Area. The population was 762 at the 2000 census but has fallen to 575 with the 2010 census....

, across the North Branch of the Potomac River from Cumberland, Maryland

Cumberland, Maryland

Cumberland is a city in the far western, Appalachian portion of Maryland, United States. It is the county seat of Allegany County, and the primary city of the Cumberland, MD-WV Metropolitan Statistical Area. At the 2010 census, the city had a population of 20,859, and the metropolitan area had a...

. It is currently recognized as the Ridgeley Member of the Old Port Formation

Old Port Formation

The Devonian Old Port Formation is a mapped bedrock unit in Pennsylvania, Maryland, and West Virginia. Members of the unit are also mapped in New Jersey and Virginia as parts of other formations or groups.-Description:...

; it has often been called the Oriskany sandstone in the region, but that name is based on a outcrop at Oriskany Falls, New York

Oriskany Falls, New York

Oriskany Falls is a village in Oneida County, New York in the United States. The population was 698 at the 2000 census. The name is derived from a waterfall on a nearby stream....

, and its application to these Central Appalachian rocks is debatable.

Outcrops of the erosion-resistant, ridge-forming Ridgeley ("Oriskany") sandstone are conspicuous landscape features in the Ridge and Valley

Ridge-and-valley Appalachians

The Ridge-and-Valley Appalachians, also called the Ridge and Valley Province or the Valley and Ridge Appalachians, are a physiographic province of the larger Appalachian division and are also a belt within the Appalachian Mountains extending from southeastern New York through northwestern New...

 physiographic province

Physiographic province

A physiographic province is a geographic region with a specific geomorphology and often specific subsurface rock type or structural elements.A continent may be subdivided into various physiographic provinces, each having a specific character, relief, and environment which contributes to its...

 from south-central Pennsylvania through western Maryland and eastern West Virginia to Craig County

Craig County, Virginia

As of the census of 2000, there were 5,091 people, 2,060 households, and 1,507 families residing in the county. The population density was 15 people per square mile . There were 2,554 housing units at an average density of 8 per square mile...

 in western Virginia. Ridgely outcrops form part of the lateral structures of North Fork Mountain

North Fork Mountain

North Fork Mountain is a quartzite-capped mountain ridge in the Ridge and Valley physiographic province of the Allegheny Mountains of eastern West Virginia, USA...

, New Creek Mountain

New Creek Mountain

New Creek Mountain is a mountain ridge of the Ridge-and-Valley Appalachians in Grant and Mineral counties in the U.S. state of West Virginia. The mountain is named for New Creek which rises and flows along its western flanks. It is part of the Wills Mountain Anticline, with Knobly Mountain along...

, and Wills Mountain

Wills Mountain

Wills Mountain is a quartzite-capped ridge in the Ridge and Valley physiographic province of the Appalachian Mountains in Pennsylvania and Maryland, USA, extending from near Bedford, Pennsylvania to near Cumberland, Maryland...

 of the Wills Mountain Anticline

Anticline

In structural geology, an anticline is a fold that is convex up and has its oldest beds at its core. The term is not to be confused with antiform, which is a purely descriptive term for any fold that is convex up. Therefore if age relationships In structural geology, an anticline is a fold that is...

, although it is the even more erosion-resistant Silurian

Silurian

The Silurian is a geologic period and system that extends from the end of the Ordovician Period, about 443.7 ± 1.5 Mya , to the beginning of the Devonian Period, about 416.0 ± 2.8 Mya . As with other geologic periods, the rock beds that define the period's start and end are well identified, but the...

-aged Tuscarora Quartzite

Tuscarora Formation

The Silurian Tuscarora Formation — also known as Tuscarora Sandstone or Tuscarora Quartzite — is a mapped bedrock unit in Pennsylvania, Maryland, West Virginia, and Virginia.-Description:...

, not the Ridgely sandstone, that caps most parts of the prominent central ridge of this long geological structure. Other conspicuous Ridgeley outcrops include Caudy's Castle (Castle Rock)

Caudy's Castle

Caudy's Castle is a rock pinnacle of Ridgeley sandstone that stands 1,400 feet above sea level over the Cacapon River near the Bloomery Pike south of Forks of Cacapon in Hampshire County, West Virginia...

 and Ice Mountain

Ice Mountain

Ice Mountain is a mountain ridge and algific talus slope that is part of a preserve near the community of North River Mills in Hampshire County, West Virginia, United States....

, both in Hampshire County, West Virginia

Hampshire County, West Virginia

Hampshire County is a county located in the U.S. state of West Virginia. As of 2010, the population was 23,964. Its county seat is Romney, West Virginia's oldest town . Hampshire County was created by the Virginia General Assembly on December 13, 1753, from parts of Frederick and Augusta counties ...

.

At Berkeley Springs, West Virginia, warm water flows from natural mineral springs

Mineral Springs

Mineral Springs is the name of several locations in the United States:* Mineral Springs, Arkansas* Mineral Springs, North Carolina* Mineral Springs Township, North Dakota* Mineral Springs at Green Springs, Ohio...

 in the Ridgeley sandstone of Warm Springs Ridge; spa facilities (now in Berkeley Springs State Park

Berkeley Springs State Park

Berkeley Springs State Park is a state park located in the center of Berkeley Springs, West Virginia. The centerpieces of this park are the spa facilities. These waters are currently and historically billed as having medicinal or restorative powers, generally taken internally for digestive...

) have long used these waters.

The Ridgeley sandstone is sometimes quarried

Quarry

A quarry is a type of open-pit mine from which rock or minerals are extracted. Quarries are generally used for extracting building materials, such as dimension stone, construction aggregate, riprap, sand, and gravel. They are often collocated with concrete and asphalt plants due to the requirement...

 and crushed to produce quartz sand for glass-making

Glass

Glass is an amorphous solid material. Glasses are typically brittle and optically transparent.The most familiar type of glass, used for centuries in windows and drinking vessels, is soda-lime glass, composed of about 75% silica plus Na2O, CaO, and several minor additives...

; one such quarry is near Berkeley Springs.