Metal abrasion

For my MA project I want to study the abrasive potential of a plant
on metal surfaces. I would like to hear suggestions on the
methodology I could use to quantify and evaluate how abrasive is
this material on metal samples.  For the moment I have only found an
article  written by Glenn Wharton, Susan Lansing Maish and William
S. Ginell which is titled "A comparative study of silver Cleaning
Abrasives" where they used the Knoop hardness measurement system,
but I would like to have other possibilities.


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                  Conservation DistList Instance 22:60
                 Distributed: Saturday, April 18, 2009
                       Message Id: cdl-22-60-016
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