Sealant or coating for marble

David Turnbull <dturnbull [at] edmontonarts__ab__ca> writes

>We have an upcoming large scale artwork that will be carved from
>Vermont Mountain White Marble and Vermont Danby Marble with a honed
>finish. It will be permanently displayed indoors in a heavily
>trafficked public space. The artist has recommended using a water-
>based penetrating sealant to protect and facilitate easier cleaning
>from water and oil-based staining. I am concerned about its
>irreversibility. Anyone with experience with successes or failures
>of penetrating sealants or opinions on coatings that could be
>applied before it is installed would be appreciated. ...

The Elgin Marbles in the British Museum are coated with
Polyethyleneglycol Wax 6000. The wax was dissolved in industrial
methylated spirit for application by brushing. This was carried
out--I think--in the 1970s. In response to the publication of  "Lord
Elgin and the Marbles: The Controversial History of the Parthenon
Sculptures" by W St Clair (Oxford, 1998), the British Museum held a
conference, in that year, to which St Clair was invited (and which
notoriously ended in chaos). However to prove a point regarding
their wellbeing, I uncovered a small square--about 10cm x 10cm--from
one of the Parthenon Frieze panels. The wax came away effortless
with IMS and revealed a slightly whiter patch of marble. The slight
darkening was due to the absorption of atmospheric dust, by the wax.

I also recall removing ink that had been squirted from a fountain
pen on a marble relief, also coated with PEG 6000. It was in the
gallery next to the Duveen Gallery (which contains the Parthenon
Frieze). The ink came off easily and had not penetrated the wax.

Eric Miller
retired from the British Museum


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                  Conservation DistList Instance 24:40
               Distributed: Wednesday, February 23, 2011
                       Message Id: cdl-24-40-002
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