The next stop is the Lincoln Memorial, 1.8 kilometers (a little more than a mile) northeast of the Jefferson
Memorial.
Lincoln Memorial -- Site 6
The Lincoln Memorial, dedicated in 1922, is made of marble from Colorado. This building has few
alteration crusts, in part because it receives regular cleaning and in part because of the design of the
building. Except for the features around the entablature (the edge of the roof) there are few sheltered areas
where alteration crusts can accumulate. With the aid of binoculars, you can see some alteration crusts
along the underside of the roof overhang; in these places the marble is very badly crumbled under the
alteration crusts. Some columns show preferential weathering or loss of inclusions, but some of this
damage might be from graffiti removal. The most visible dissolution feature is sugaring, where the stone
has lost its polish and the surface now feels rough. Visitors have affected this popular memorial too;
several of the columns, especially the limestone columns inside the chamber, show darkening and rounding
of edges where visitors have touched them over the years.
One interesting feature at the Lincoln Memorial is differences in stone condition that must come from
variations in the stone. At several places around the outside of the memorial, adjacent blocks of marble
show very different surface roughness. Since the blocks of stone have the same orientation with respect to
wind, rain, and pollution, the difference in condition cannot be due to exposure and must be related to basic characteristics in the stone that was used.
The Lincoln Memorial is made of marble and was dedicated in 1922.
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| Under the roof overhang is one of the few places at the Lincoln Memorial where
alteration crusts have
developed on the marble.
|
Some columns at the Lincoln Memorial have flattened chalky areas where
inclusions have weathered
differently from the surrounding calcite.
|
|
| The marble guttae on the roof overhang are crumbling and falling apart
underneath blackened alteration crusts.
|
Sites 5-8
Map of All Sites on the Tour
[102 K image]
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Last modified 07.21.97