URAL MINERALOGICAL FESTIVAL, July 3 to 21, 2019, in Yekaterinburg City, Ural region, Russia
Welcome to the GemologyOnline.com Forum
A non-profit Forum for the exchange of gemological ideas
It is currently Tue Jun 25, 2019 7:44 am

All times are UTC - 4 hours




Post new topic Reply to topic  [ 28 posts ]  Go to page Previous  1, 2
Author Message
 Post subject: Re: Seperating Saltwater and Freshwater Pearls
PostPosted: Fri Aug 03, 2012 4:20 am 
Offline
Gemology Online Übergod
User avatar

Joined: Tue Aug 01, 2006 3:24 am
Posts: 4997
Location: McDonough GA
Ok, what is this? People promising to test but never get to it? Is this a STRIP TEASE??? ;)

_________________
http://www.selectgem.com


Top
 Profile  
Reply with quote  
 Post subject: Re: Seperating Saltwater and Freshwater Pearls
PostPosted: Fri Aug 03, 2012 6:34 am 
Offline
Valued Contributor
User avatar

Joined: Tue Oct 20, 2009 3:34 pm
Posts: 381
Location: Sweden
:lol: :lol: :lol:

_________________
~~~Lennie~~~


Top
 Profile  
Reply with quote  
 Post subject: Re: Seperating Saltwater and Freshwater Pearls
PostPosted: Fri Aug 03, 2012 11:28 pm 
Offline
Valued Contributor

Joined: Mon Oct 17, 2005 11:10 am
Posts: 287
Location: Illinois
That's ok, take your time. I'll just keep guessing. What's the worst that can happen? :lol:

_________________
I love the smell of Methylene Iodide in the morning...


Top
 Profile  
Reply with quote  
 Post subject: Re: Seperating Saltwater and Freshwater Pearls
PostPosted: Thu Aug 30, 2012 3:40 pm 
Offline
Valued Contributor

Joined: Sat Aug 25, 2012 3:45 am
Posts: 134
Location: Kuala Lumpur, Malaysia
I am a pearl fan, and I have heard of this test before. But to do such a potentially aggressive test on any pearl.....I can't :(

In my opinion, as long as the pearl is of top condition (nice luster, nice surface condition, good color, nice shape with good size), I don't really care about whether it is from the sea or from the freshwater. Chinese freshwater pearls are really amazing lately! From the ulcerous looking seed pearls about 2 decades ago to the currently nice, huge, round or near round pearls that are as good as (or may be better than) certain saltwater pearls! Such freshwater pearls are made up of full nacre and are theoretically more durable than the cultured pearls with thin layer of nacre. And they are much cheaper :mrgreen: !

Anyway, differentiation between the saltwater and freshwater origin may be very important for the pearl market (judged by the huge price difference).......then go ahead.... :cry:

Nevertheless, I do notice that the "color play" of freshwater pearls is usually different from the seawater pearls. Freshwater pearls are usually made up of 100% nacre, resulting in very characteristic "rainbow color play effect" that you hardly see on seawater pearls....On the other hand, south sea pearls tend to show the soft, silky shine kinda luster. Even when the nacre is very thick, the "rainbow color play" is still very soft. And this soft glow of south sea pearls is seen in any color forms. I am not familiar with Akoya as for unknown reasons, I just not interested in Akoya... 8)

Attached are some pictures form my collection of freshwater and south sea pearls. They may be helpful to highlight the optical differences between the pearls.

But again, a great pearl is a fabulous gem regardless of its origin....

Regards,
WCLee


Attachments:
3 golden south seas.jpg
3 golden south seas.jpg [ 90.85 KiB | Viewed 3973 times ]
silver south sea.jpg
silver south sea.jpg [ 98.1 KiB | Viewed 3973 times ]
freshwater.jpg
freshwater.jpg [ 76.59 KiB | Viewed 3973 times ]
Top
 Profile  
Reply with quote  
 Post subject: Re: Seperating Saltwater and Freshwater Pearls
PostPosted: Tue Sep 04, 2012 10:43 pm 
Offline
Valued Contributor

Joined: Sun Mar 08, 2009 2:16 pm
Posts: 330
We get clear results on XRF. As Barbra stated, the Mn content is the giveaway on FWP.
Bear


Top
 Profile  
Reply with quote  
 Post subject: Re: Seperating Saltwater and Freshwater Pearls
PostPosted: Thu Nov 29, 2012 10:12 am 
Offline
Valued Contributor
User avatar

Joined: Wed Apr 18, 2007 4:38 am
Posts: 142
Location: New Delhi,India
Does this test fits on Fresh Water Natural pearls also? or only on cultured fresh water pearls?

_________________
Money demands that you sell, not your weakness to men's stupidity, but your talent to their reason.


Top
 Profile  
Reply with quote  
 Post subject: Re: Seperating Saltwater and Freshwater Pearls
PostPosted: Thu Nov 29, 2012 10:29 am 
Offline
Valued Contributor

Joined: Sun Mar 08, 2009 2:16 pm
Posts: 330
KS- This test would give you the same result for FWCP and FWNP. Xray fluorescence is used to reveal the chemistry on the outer parts of the pearl. What you need for distinguishing nat vs cultured is to view an X-ray photo to look at the inside. Is this the answer you were hunting?


Top
 Profile  
Reply with quote  
 Post subject: Re: Seperating Saltwater and Freshwater Pearls
PostPosted: Thu Nov 29, 2012 2:56 pm 
Offline
Valued Contributor
User avatar

Joined: Wed Apr 18, 2007 4:38 am
Posts: 142
Location: New Delhi,India
Bear Williams- SGL wrote:
KS- This test would give you the same result for FWCP and FWNP. Xray fluorescence is used to reveal the chemistry on the outer parts of the pearl. What you need for distinguishing nat vs cultured is to view an X-ray photo to look at the inside. Is this the answer you were hunting?

thanks for writing in,X-ray florescence does show a bright blue line when pearls are exposed to it.
but similar results occur when salt water pearls are exposed to it though in salt water pearls case it don't happen with all of them.
i wanted to know if magnesium test fits on both natural fresh water pearls and cultured fresh water pearls?
do you mean x ray florescence shows high magnesium on pearl's surface?

_________________
Money demands that you sell, not your weakness to men's stupidity, but your talent to their reason.


Top
 Profile  
Reply with quote  
 Post subject: Re: Seperating Saltwater and Freshwater Pearls
PostPosted: Thu Nov 29, 2012 3:36 pm 
Offline
Valued Contributor

Joined: Sun Mar 08, 2009 2:16 pm
Posts: 330
Yes, the ED-XRF test would give you the same magnesium result for both FWCP and FW naturals. The Mn is just a trace element and exists throughout the nacre of all these FWP. XRF is pretty much a surface reading, and as you can imagine the calcium accounts for most %. :smt051 off to catch a plane... bw


Top
 Profile  
Reply with quote  
 Post subject: Re: Seperating Saltwater and Freshwater Pearls
PostPosted: Sat Dec 01, 2012 10:59 pm 
Offline
Valued Contributor
User avatar

Joined: Wed Jun 15, 2011 8:29 am
Posts: 123
Location: London
That acid test got me thinking but about pearls I know next to nothing so I wonder if some experts could say if there's a procedure of restoring damaged pearls (if not damaged too deep of course). Theoretically you could remove damaged layers until you have undamaged one on top...

_________________
Treasurion Gems & Jewellery

Gems & Jewellery Blog

Top
 Profile  
Reply with quote  
 Post subject: Re: Seperating Saltwater and Freshwater Pearls
PostPosted: Sun Apr 14, 2013 8:38 pm 
Offline
Valued Contributor

Joined: Mon Oct 17, 2005 11:10 am
Posts: 287
Location: Illinois
Spent an couple of days in Chicago at the Smart Shoe (Instore Magazine show). There was a gentlemen selling a gun type tester for scrapping precious metals in on of the tool booths. After watching it for a bit I went a borrowed a strand of salt water pearls and a strand of freshwater. The freshwater had 840ppm Manganese which was picked up in 25 seconds with no damage to the pearls. Unit was a bit pricey (17000.00) but I am guessing that besides giving you the exact content of your scrap, it would also be able to pick up the trace elements of black dyes in pearls and maybe even the agents they use to cost the bottom of some of the gemstones ( I know some have a gold content). http://www.oxford-instruments.com/produ ... 000-series
Since I haven't seen any results on the separation proposed by Dr. Hanni, I assume that it doesn't work or is not feasible. Has anybody heard anything else since last fall?

_________________
I love the smell of Methylene Iodide in the morning...


Top
 Profile  
Reply with quote  
 Post subject: Re: Seperating Saltwater and Freshwater Pearls
PostPosted: Tue Oct 28, 2014 12:08 pm 
Offline
Established Member

Joined: Mon Jul 30, 2012 1:21 pm
Posts: 16
I would love to hear more; our customers are constantly asking if our cultured pearls are freshwater or saltwater.


Top
 Profile  
Reply with quote  
 Post subject: Re: Seperating Saltwater and Freshwater Pearls
PostPosted: Wed Oct 26, 2016 9:47 pm 
Offline
Valued Contributor

Joined: Mon Oct 17, 2005 11:10 am
Posts: 287
Location: Illinois
Been a while. Did anybody ever follow up on the test strips for Manganese? Freshwater pearls are getting better and harder to distinguish beaded material.

_________________
I love the smell of Methylene Iodide in the morning...


Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 28 posts ]  Go to page Previous  1, 2

All times are UTC - 4 hours


Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group
Gemology Style ported to phpBB3 by Christian Bullock