Building Stones of Maryland

A building stone is defined as any massive, dense rock suitable for use in construction. Whether igneous, metamorphic or sedimentary, a building stone is chosen for its properties of durability, attractiveness, and economy. A dimension stone is a building stone that is often quarried and prepared in blocks according to specifications. A decorative stone is a stone that can be quarried, cut or carved and is most highly valued for its pleasing appearance. It is more often used in interior construction for decoration and monuments than as standard building stone.

There are a number of rocks in Maryland that have, at one time or another, been used as building or decorative stone. The earliest settlers used local fieldstone to build their houses. Later, as the demand grew for more elegant buildings and monuments, stone was sought which was both durable, and attractive. From the 1840's to the early 1900's, there were many quarries opened in Maryland for the various types of building or decorative stones described herein. The dimension, building, and decorative stone industries today are almost non-existent because of competition from other, lower cost materials. Only the Setters Quartzite, the Sykesville Gneiss, and some Paleozoic sandstones are currently being quarried.

The first four "granites" and gneisses that are discussed were frequently used in buildings around Baltimore. In descriptions of buildings,these stones have often been confused, but with careful observation, the differences between them can easily be noted.

• Port Deposit "Granite"..... a coarse-grained, granite gneiss with an obvious foliation produced by black mica. The rock was used in early days by colonial settlers, but commercial use did not occur until about 1816 when stone was needed for the abutments to the Susquehanna River Bridge. A quarry was established at Port Deposit and by the 1830's much of the stone was being shipped to Baltimore. Other quarries were opened in Cecil County as the stone gained acceptance. Some of the buildings in which this popular stone was used are: Fort Carroll, Fort McHenry, the Naval Academy in Annapolis, Haverford College in Philadelphia, and part of the old Goucher College in Baltimore. It is now quarried north of Havre de Grace by the Arundel Corporation for use as crushed stone.
• Baltimore Gneiss..... any of several similar looking banded gneisses in a variety of colors, texture, and composition that were quarried along the Jones Falls and Gwynns Falls in Baltimore City. It is thought that the first buildings of Baltimore in the 1700's used stone quarried from the Jones Falls gneiss, near the old Mount Royal railroad shops. Many of the tone buildings, foundations, roads, and curbstones in Baltimore were built of rock from both the Jones Falls and Gwynns Falls quarries. The blue-gray color of fresh stone caused the term "blue stone" to be used by the quarrymen. The last building stone quarry in Baltimore closed in 1958.
• Ellicott City "Granite"..... a porphyritic gneiss that was first quarried in the late 18th century. It was used in building the Basilica of the Assumption in Baltimore, which was erected during the period 1806 to 1821. Material was hauled from the Ellicott City area to Baltimore by huge wagons drawn by nine yoke of oxen. After 1892, the stone was used primarily in foundations and as paving stone. Little building stone was produced from this area after 1896.
• Woodstock Granite..... a pinkish-toned, coarse-grained, gray granitic rock that was quarried near the town of Granite in Baltimore and Howard counties. This rock was first quarried in 1832 and was used intermittently until the 1920's. It was employed as a monument stone as well as being used for building exteriors. Buildings made from this stone include: parts of the Capitol building and the Library of Congress in Washington, D.C., the Baltimore Customs House, and the old Baltimore County Court House. Many curbstones, paving blocks and bridges are made of this stone.
• Cockeysville Marble... a white, crystalline, metalimestone, most famous for its use in the Washington Monument in Washington, D.C. The first 152 feet of the monument, built between 1845 and 1854, were faced with Cockeysville stone from a quarry near Texas, about 12 miles north of Baltimore. When funds were depleted, work ceased for 25 years and was resumed again in 1879 using a marble from Lee, Massachusetts. Four courses of this stone were used; however, it proved too costly and the remainder of the structure was faced with marble from a quarry in the Cockeysville area. The marble was also used in the construction of the Washington Monument in Baltimore City. By the 1840's-1850's, the marble was very popular and readily available for use in building the stone front steps of many of the older row houses in Baltimore. The Beaver Dam quarry at Cockeysville furnished marble used for the 108 columns in the wings of the National Capitol at Washington, D.C. Today, quarries work the Cockeysville Marble primarily for crushed stone and high-purity calcite.
• Slate..... a bluish-gray, thin-bedded, fade resistant slate was quarried from the Peach Bottom-Cardiff area in Harford County and, to a lesser extent,from the Ijamsville area in Frederick County. The Peach Bottom area was worked as early as 1750 for local use. The first commercial Peach Bottom quarry opened in 1812, about the same time that work began in the Ijamsville area. The Ijamsville slates did not achieve the popularity afforded those from Peach Bottom because of their dullness and softness or lack of "ring," and operations closed in 1892. Slate was quarried from Peach Bottom as late as 1957 for granules in composition roofing shingles.
• "Seneca Red" Sandstone..... a reddish to purplish brown, fine-grained, arkosic sandstone or "Brownstone" was quarried extensively along the Potomac River in Montgomery and Frederick Counties. This Triassic stone was initially used for the "Potowmack Canal" built around 1774 and again for the C & O Canal in the early 1830's. It became a popular building stone during the period between 1840 and 1889. Many buildings in Washington, D.C., and in Baltimore were constructed of brownstone. In 1847, it was used to build the Smithsonian Institution Building in Washington, D.C. The stone is readily carved and chiseled when first quarried but later hardens on exposure to air. There is a tendency of the rock to spall if laid "on edge," therefore, careful placement was required.
• "Potomac Marble"..... also known as "calico rock" or "Potomac Breccia," is a multi-colored conglomerate of Triassic age and is composed of rounded quartz and limestone pebbles cemented in a calcareous matrix. Benjamin Latrobe first reported finding this rock in 1815. This stone, probably quarried from Montgomery County, was used for the twenty-foot columns in the old U.S. House of Representatives (now Statuary Hall). It proved to be difficult to work because of the differing hardness of the pebbles and matrix and thus never attained widespread use. The stone was quarried primarily in Frederick County, most extensively along the Potomac River, near Washington Junction. One company intermittently worked this stone as late as 1898.
• Wakefield Marble..... a variegated marble used for altar fronts and interior decorations was quarried in Carroll and Frederick Counties. The colors range from "deep red," "salmon," "lavender veined," "undulated pink and white," "ruby" to black to white. The marble's variety of color was its drawback, as it was neither consistent nor predictable. The marble was worked around the turn of the 20th century.
• Serpentinite..... a patterned rock occurring in various shades of green from pale leek to greenish black that has been used both as a building stone and as a sawed and polished ornamental stone. Serpentinite from Baltimore County was used to build the Mount Vernon Place Methodist Church in Baltimore City. Cut and polished, it is also known as "Maryland Green Marble" or "verde antique." It was extensively quarried near Cambria and Broad Creek in Harford County as early as 1870. Stone from Broad Creek was shipped to New York and was used in the Empire State Building in New York City. This stone was also crushed for use in terrazzo flooring in the early 1970's. A recent attempt to reopen the quarry in Cambria failed.
• Sykesville Gneiss..... a dark gray, often schistose gneiss with a roughly rectangular fracture pattern is currently being quarried near Potomac in Montgomery County and was at one time used extensively in the Washington, D.C. area for foundation and rubble stone. The stone was first worked commercially as "granite" about 1850. The early settlers in the Washington area used many of the schists and gneisses found along the PotomacRiver. This Sykesville stone may be what was once known as "Potomac Bluestone."
• Setters Quartzite..... a thinly layered tan quartzite that has been used for many years as a flagstone and as building material. Tourmaline crystals are often present on cleavage surfaces. The stone has become popular in recent years for use in many of the houses and buildings in Towson and Baltimore. It is currently being quarried near Marriottsville in both Howard and Baltimore Counties.
• Paleozoic Sandstones..... four sandstone beds which range in age from Silurian to Mississippian have been quarried in Western Maryland for use in that area. The Tuscarora sandstone has been used for foundation stones and trim in many of the older buildings at Cumberland. The Oriskany, a yellow to buff sandstone was also widely used there; however the stone is soft and tends to disintegrate with time. Currently, both the Pocono, a thin-bedded brown sandstone, and the Pottsville, a massive gray conglomeratic sandstone, have limited use for flagstone, building facing, and rubble stone.

Many other rock formations were used throughout Maryland for building material. Often these were simply rocks picked up near the site of construction and are termed "fieldstone." Initially, most building stone was obtained this way, but about 1825 technology and transportation had developed to the point that it was feasible to quarry stone at specific sites. In addition to the better know quarries, many small quarries sprang up throughout Maryland to satisfy the local demand. Even after the better building stones became everywhere available, it often proved to be economic to use field stone and local quarry rubble for hidden foundation work. Before the era of the massive stone buildings abated, stone was imported from as far as Indiana. The Baltimore Museum of Art, completed in 1929 was made from Indiana limestone.

The building stone industry of Maryland in recent years has diminished in importance. New construction technology, together with a less labor-intensive economy and modern architectural leanings have reduced the demand for stone. Ample deposits of stone are still available, but present trends do not indicate a revival of the building stone trade in the foreseeable future.

SELECTED REFERENCES

Dorsey, J. and Dilts, J.D., 1981, A guide to Baltimore architecture: Tidewater Pub., Centreville, Md., 267 p.

Edwards, J., Jr., 1969, Mineral resources of Harford County, in The geology of Harford County, Maryland: Md. Geol. Survey, p. 104-111.

Gary, M., McAfee, R., Jr., and Wolf, C.L., 1972, Glossary of geology: Amer. Geol. Institute, Washington, D.C., 805 p.

Geyer, A.R., 1977, Building stones of Pennsylvania's capital area: Pa. Geol. Survey, Env. Geol. Rpt. 5, 46 p.

Kuff, K.R., 1980, Directory of mineral producers in Maryland 1970: Md. Geol. Survey, Inf. Cir. 30, p. 22-23.

Mathews, E.B. and Watson, E.H., 1929, The mineral resources of Baltimore County, in Baltimore County: Md. Geol. Survey, p. 219-288.

Merrill, G.P. and Mathews, E.B., 1898, The building and decorative stones of Maryland: Md. Geol. Survey, Vol. 11, Pt. 2, p. 47-241.

Vokes, H.E. and Edwards, J., Jr., 1974, Geography and geology of Maryland: Md. Geol. Survey, Bull. 19, p. 116-123.

Watson, T.L., 1910, Granites of the southeastern Atlantic states: U.S. Geol. Survey, Bull. 426, p. 39-69.

Winkler, E.M., 1975, Stone: properties, durability in man's environment: Springer-Verlag, New York, 193 p.

Winkler, E.M., ed., 1978, Decay and preservation of stone: Geol. Soc. of Amer., Eng. Geol. Case Hist. II, 102 p.

Withington, C.F., 1975, Building stones of our nation's capital: U.S. Geol. Survey, 44 p.

This pamphlet was prepared by by Karen R. Kuff and James R. Brooks, 1990
Compiled by the Maryland Geological Survey, 2300 St. Paul Street, Baltimore, MD 21218
This electronic version of "Building Stones of Maryland" was prepared by Bob Conkwright, Division of Coastal and Estuarine Geology, Maryland Geological Survey. Please send comments on this page to Dale Shelton (dale.shelton@maryland.gov)