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Continue east along C street to Memorial Continental Hall.

DAR -- Memorial Continental Hall -- Site 10

Memorial Continental Hall
Memorial Continental Hall, built in 1909, is part of the Daughters of the American Revolution building complex.

The porch area on the south side of this marble building built in 1909 is a good place to look at some contrasts in marble deterioration. Parts of the balustrade have been replaced, as shown by differences in color and surface roughness of the stone. The exposed stone surface along the top of the balustrade is rougher than the surfaces in more sheltered areas. The columns on this porch are carved around the base, so you can examine the effects of exposure to rain on the carving details. The more exposed carvings have lost their sharp edges and definition compared to the sheltered carvings. The bases of the columns contain small amounts of pyrite, which is more resistant to weathering than is the calcite in the marble surrounding the pyrite. The sheltered part of the windowsill support on the west side of the porch shows an alteration crust, a dull gray accumulation on the stone surface.

Carved details at the Hall
Carvings at the base of the columns on the south side of Memorial Continental Hall show that carved details and sharp edges remain on sheltered areas.

Rounded marble edges Pyrite grains in relief Beginning of alteration crust
On an exposed portion of the carving on the columns at Memorial Continental Hall, the edges of the marble have rounded and the surface has roughened. Pyrite grains stand in relief where calcite and micas have weathered out of the marble at Memorial Continental Hall. A dull gray surface on the marble on the window sill support shows where an alteration crust is just beginning to develop.

sites 9-14
Sites 9-14

Map of All Sites on the Tour [102 K image]

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Last modified 07.21.97