Clearing snow and ice from marble steps

Barbara Appelbaum <aandh [at] mindspring__com> writes

>A client of ours has asked about the problem of clearing snow and
>ice from marble steps.  She knows that salt should not be used.  Is
>it possible to apply coatings in advance that will mitigate the
>possible effects of salt, or is there something else--ash or sand,
>perhaps--that is not harmful to marble?

I notice that the Canadian Conservation Institute's Guide to Closing
a Museum for Winter

    <URL:http://www.cci-icc.gc.ca/crc/notes/html/1-3-eng.aspx>

states:

   "Snow Removal The problem of snow and ice can be simplified by
    their immediate clearance; prevent build-up. Snow-blowers and
    blade-type removal equipment will chip and scrape historic
    materials such as cobblestone, brick, and stone pavement. The
    practice of using salt can initiate corrosive action on brick,
    concrete, and metal. A mixture of crushed limestone and urea
    powder, which helps to keep walkways clear but does not cause
    efflorescence, is available commercially."

Has anyone tried the limestone and urea mix on marble? Does anyone
know the name of any commercial products?  Does cat litter help?
Many people in the UK tried the clay type of cat litters to help get
cars safely over icy roads this winter.  I have also seen pelletised
lime and calcium magnesium acetate suggested as deicers (and
electric heating mats which have to be installed under the marble
when the stairs are built).

Hope this helps,

Helena Jaeschke
Conservation Development Officer
Royal Albert Memorial Museum
Exeter Ark
3 Exton Road
Marsh Barton
Exeter EX2 8LX
+44 1392 665951


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                  Conservation DistList Instance 23:40
                  Distributed: Friday, April 16, 2010
                       Message Id: cdl-23-40-002
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