Pearl-Guide.com - Pearl Forum - Pearling Industry News http://www.pearl-guide.com/forum/ en Sun, 19 May 2013 11:26:50 GMT vBulletin 60 http://www.pearl-guide.com/forum/images/Eloquent/miscblue/rss.png Pearl-Guide.com - Pearl Forum - Pearling Industry News http://www.pearl-guide.com/forum/ <![CDATA[Who wants to visit Jewelmer's pearl farm?]]> http://www.pearl-guide.com/forum/showthread.php?t=7707&goto=newpost Wed, 15 May 2013 21:31:31 GMT Jewelmer and the CPAA have teamed up to send two people to Flower Island in the Philippines, but they are having a hard time selling tickets to the raffle. I've decided to help by buying them up and giving them away.

If anyone is interested in free golden tickets ... http://blog.pearlparadise.com/2013/0...ppines-anyone/ ]]> Pearling Industry News jshepherd http://www.pearl-guide.com/forum/showthread.php?t=7707 Japan, Bahrain to explore reviving pearl industry in Persian Gulf http://www.pearl-guide.com/forum/showthread.php?t=7677&goto=newpost Thu, 02 May 2013 22:11:23 GMT Researchers from both Japan and Bahrain will conduct joint research this year on pearl oysters from off the Middle Eastern nation’s coast, with the hope of reviving the traditional industry from Persian Gulf. ... Researchers from both Japan and Bahrain will conduct joint research this year on pearl oysters from off the Middle Eastern nation’s coast, with the hope of reviving the traditional industry from Persian Gulf.

http://japandailypress.com/japan-bahrain-to-explore-reviving-pearl-industry-in-persian-gulf-0128036 ]]> Pearling Industry News jshepherd http://www.pearl-guide.com/forum/showthread.php?t=7677 Basidiomycota perlus or the strange mushroom pearl http://www.pearl-guide.com/forum/showthread.php?t=7623&goto=newpost Mon, 22 Apr 2013 00:23:00 GMT SSEF 2013. Attachment 22609 (http://www.pearl-guide.com/forum/attachment.php?attachmentid=22609) In 2012, we again received a number of pearls with strange shapes for testing. The most extravagant and intriguing of these curiosities of nature was a non-nacreous brownish natural pearl from a... SSEF 2013.

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In 2012, we again received a number of pearls with strange shapes for testing. The most extravagant and intriguing of these curiosities of nature was a non-nacreous brownish natural pearl from a marine mollusc, which closely resembled a mushroom (see photos). The pearl showed some flame structures, as it is known from various gastropods such as Melo Melo, Strombus Gigas (Queen Conch), Cassis Cornuta, and clams (Tridacna). X-ray microtomography analysis showed a complex structure of growth layers surrounding a central cavity, rather uncommon for such non-nacreous natural pearls.
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]]> Pearling Industry News Cyril Roger Brossard http://www.pearl-guide.com/forum/showthread.php?t=7623 Radiocarbon age dating of pearls http://www.pearl-guide.com/forum/showthread.php?t=7622&goto=newpost Mon, 22 Apr 2013 00:15:31 GMT As seen in the FACETTE of 2013. Apart from constantly updating our equipment for our scientific pearl testing procedure, we also invest much effort evaluating new scientific approaches for pearl characterisation and testing. In this context, we started a research project a few years ago in... As seen in the FACETTE of 2013.

Apart from constantly updating our equipment for our scientific pearl testing procedure, we also invest much effort evaluating new scientific approaches for pearl characterisation and testing.

In this context, we started a research project a few years ago in collaboration with Dr. Irka Hajdas (ETH Zurich) to investigate the possibilities of radiocarbon age dating of pearls. This method uses naturally occurring isotope 14C to determine the age of carbonaceous materials up to 60’000 years.
Last year saw some interesting developments, as we were able to analyse a batch of pearls that spanned from the 18th century to today. The results of this research were presented by M.S. Krzemnicki at the 21st International Radiocarbon Conference, held in the prestigious UNESCO building in Paris (9-13th July 2012).
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Pearls - being calcium carbonate (CaCO3) concretions formed by biomineralization in molluscs - contain traces of radiogenic 14C. Similar to age dating of bones or tissues or other artefacts, a tiny amount of pearl nacre (ca. 8 mg) was scratched/peeled off from the surface of the pearls and investigated using the ultra-sensitive Accelerator Mass Spectrometry (AMS) technique at the Laboratory of Ion Beam Physics, Swiss Federal Institute of Technology (ETH Zurich) in Zurich. A general problem of our data is that marine reservoir ages may strongly affect the resulting radiocarbon ages of shells, and consequently also pearls, especially in areas with upwelling of “old” seawater. As could be shown, it is usually not possible to gain a reasonable radiocarbon age for freshwater pearls (and shells). This is due to the incorporation of sedimentary limestone into the biomineralized calcium carbonate (socalled “hard-water effect”), which then may strongly affect the resulting data (Bezzerra et al. 2000). However, for suspension-feeding saltwater molluscs (e.g. oysters), such as our studied samples from Pinctada maxima and Pinctada radiata, which live in coastal marine habitats with known upwelling and carbon isotope ratios, the analyses should result in more or less reliable radiocarbon ages (Taylor & Slota 1979, Bezzerra et al. 2000, Rick et al. 2005).
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The most important feature for pearl age testing is the so-called bomb peak calibration curve, a major and sudden increase in 14C ratio around 1965, followed by an exponential decreasing tail, as a consequence of the atmospheric nuclear bomb testing in the 50s and 60s of the 20th century. By superposing the bomb peak to the progress of the cultured pearl industry, we were able to separate our saltwater pearl samples into two main categories: pearls which are distinctly older than the bomb peak (before 20th century), and which therefore are most likely to be natural pearls, and pearls whose age is close to or later than the bomb peak. Pearls from the second category are either natural or cultured. Finally, an identification of the nature (natural vs. cultured) of these pearls is still based on the “classical” approach using radiography and μ-tomography.
Based on these promising results, a further study with more pearls is planned for the near future. Although there are many factors which may influence radiocarbon data of pearls and which are not well understood so far, it will be of strong interest for us to study further well-documented pearls of historic or recent age. This will give us a better picture about possibilities and restrictions of this method. Though this is so far not intended as a commercial service fo our clients, we will inform our members as soon as such a testing service is feasible.
Any reader who would like to contribute to this research by supplying well-documented pearls is highly welcome to contact Dr. Michael S. Krzemnicki at SSEF. An article about our findings has been submitted to the Radiocarbon Journal and will be published soon...
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]]> Pearling Industry News Cyril Roger Brossard http://www.pearl-guide.com/forum/showthread.php?t=7622 <![CDATA[History of pearls to wow at autumn V&A exhibition]]> http://www.pearl-guide.com/forum/showthread.php?t=7605&goto=newpost Fri, 19 Apr 2013 23:21:55 GMT As seen in Professional Jeweller of April 18 2013.

The V&A museum in London is set to host a large-scale historical exhibition of more than 200 pieces of pearl jewellery and pearl objets d'art.

The showcase will open in September with an array of historical pearl jewellery, artwork and objects including tiaras worn by European nobility and cultured pearls owned by Marilyn Monroe.

The exhibition, titled Pearls, promises to showcase "the extraordinary variety of colour and shape of natural and cultured pearls", examining how pearls have been used over the centuries in both Eastern and Western design as a symbol of status and wealth.

It will explore Mikimoto's cultured pearl process and the history of pearl fishing, as well as Carl Linnaeus' 18th century experiments used to produce cultured pearls.

Pearls will take jewellery design as its central focus, showcasing pearl jewellery from ancient Rome, made as early as the first century AD, through to pieces created using melo pearls in 2011.

There will be examples of Roman and Byzantine jewellery, Medieval pearl creations and jewels from the Renaissance period.
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Other designs include an Art Deco brooch by Jean Fouquet and figurative creations made using pearls by Geoffrey Rowlandson, as well as tiaras formerly belonging to the British and European high nobility, such as the Rosebery Tiara (pictured), and Elizabeth Taylor’s Bulgari pearl-drop earrings.

The Pearls exhibition has been organised in partnership with the Qatar Museums Authority (QMA) and will be the highlight event of the Qatar UK 2013 Year of Culture. It has been co-curated by independent jewellery historian and curator Beatriz Chadour-Sampson and Hubert Bari, director of the Pearl and Jewellery Museum at QMA.

Pearls opens on September 21 and runs until January 19 2014, with tickets priced at £10.
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]]> Pearling Industry News Cyril Roger Brossard http://www.pearl-guide.com/forum/showthread.php?t=7605