The rock serpentine is found in several shades of green - yellowish, grayish, or dark green. It has been used for building, but it has never been popular. The light-green stone houses you see in Baltimore and Harford Counties are probably made of serpentine.
Serpentine is quarried for road building. The dark green variety is used as a decorative stone. This stone has light veins running through it and polishes beautifully. Slabs of it are used for tabletops or for lining corridors in public buildings.
Known as either "verde antique" or "green marble", serpentine resembles marble. But Maryland's serpentine is not a marble chemically and has little to do with it. True marble comes from a sedimentary rock composed of limey mud or the limey remains of millions of tiny animals or larger shelled creatures. Maryland serpentine was never "alive" in this sense; in fact, it never occurs in a sedimentary form. Probably, our serpentine was originally a dark-colored igneous rock.
Serpentine is found in six Maryland counties: Montgomery, Howard, Carroll, Baltimore, Harford and Cecil. The best known quarry was at Cardiff in the northern part of our county. This quarry was very deep and produced serpentine that was prized for decorative purposes.
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email any suggestions or comments.Last updated June 24, 1997