Mineral replacement in bone

This query is posted on behalf of a colleague, Dr. Clare Ellis
<claree [at] aocscot__co__uk.>, who does not have access to the DistList.
Please respond directly to her and if of general interest post it
here as well

    A medieval site in Edinburgh has produced animal bone from all
    levels from 14th to 18th century that has had the calcium
    phosphate partially replaced with crystalline quartz. How did
    this happen? The pH of the soils hovers around neutral. Is it
    post-depositional or diet? No stone cleaning has taken place on
    site. The site after about 1800s was occupied by a coal shed for
    the gas works.


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                  Conservation DistList Instance 15:57
                 Distributed: Friday, February 15, 2002
                       Message Id: cdl-15-57-011
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