Pearls

The following is posted on behalf of Alayne Alvis

  Debra Seabrook <ecpmchin [at] execulink__com> writes

  >... I realized that the
  >dress is actively infested.  The dress is made from a blue satin
  >with lace trim and pearl accents on the lace collar and shoulders.
  >My query is in relation to the pearls.  I know they are made from
  >the same nacre material that lines the shell.  However, I can not
  >find any information that tells me whether they can be frozen with
  >the dress or do they have to be removed prior to treatment

  My gut feeling is to remove the pearls. You are correct in saying
  that they are made from the same material as nacre. The structure
  can be visualised as tiny flat bricks of calcium carbonate in a
  mortar of protein, in many, many layers.

  I did some research a few years ago on nacre and found it was
  extremely resistant to damage by exposure to wide fluctuations in
  ambient RH as well as to heating. However, I think that freezing is
  likely to cause damage to the protein component of the pearls.

  It may also be wise to check that the pearls are indeed natural
  pearls and not imitation ones. Please contact me off-list if you
  need any information about identification.

  Alayne Alvis
  Assistant Large Technology Conservator
  (also former gemmologist!)
  Australian War Memorial

George Bailey

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                  Conservation DistList Instance 12:92
                   Distributed: Friday, May 28, 1999
                       Message Id: cdl-12-92-002
                                  ***