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 Post subject: South Sea versus freshwater pearls
PostPosted: Mon Apr 15, 2019 12:32 pm 
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Joined: Mon Sep 11, 2006 7:11 am
Posts: 102
Location: Cape Town
I received a string of pearls for an appraisal and the client said they were sold as South Sea pearls for R200000 ($14250). The red flag went up due to the lustre and shape. The lustre appears to be too good for South Sea. They are a 'fat doughnut' shape and the size range is 10.50 - 11.00mm. I had them X-rayed but this was not conclusive as no nacre was clear enough to make a call. I then had a CT scan done on one of the pearls which indicates Freshwater. This will most probably end up in court, so I need to be absolutely sure of my facts.

I would appreciate any comments. Attached is a pic of the CT scan.


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 Post subject: Re: South Sea versus freshwater pearls
PostPosted: Thu Apr 18, 2019 4:43 pm 
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Joined: Wed Jan 23, 2013 5:29 pm
Posts: 1047
Location: Paris
Perhaps, a picture of the necklace and pearls might help.

If the case needs to go to court, a lab report might be necessary, to determine if the pearls are nucleated, and the chemical composition of the nacre : freshwater (with manganese) or saltwater (without).


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 Post subject: Re: South Sea versus freshwater pearls
PostPosted: Fri Apr 19, 2019 10:48 am 
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Joined: Mon Oct 17, 2005 11:10 am
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Location: Illinois
Whatever happened to the idea that there would be test strips to check for manganese?

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