Slate is one member of the metamorphic rock family to which you need no introduction. You have probably seen slate used as roofing on buildings, such as churches and homes. You may have also seen chalkboards made out of this metamorphic rock.
Slate is related to shale. Shale was once mud that had become hard through pressure. When shale is subjected to still greater pressure and heat, it is changed into slate. The process rearranges the minerals, and they line up in one plane, making slate easy to split.
Only one area in Maryland has recently produced slate, a small section in the northern part of our county in the Whiteford-Cardiff area. If you were to visit this region of our county, you would see that most of the houses have slate roofs, and many of the homes are actually built on foundations made of slate.
Sidewalks are made of big plates of slate. Even gravestones are made of slate. The town of Cardiff was named by the Welsh immigrants who came to the area to work in the slate quarries.
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email any suggestions or comments.Last updated June 24, 1997