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| Hi, I am relatively new to this forum and following this thread I can understand it can be hard to define a certain term. On the other hand, as a consumer who always like to buy the best, I would like to see terms that describe something of rarity and value be kept accurate. Quote:
For example, in the sapphire market, people who are selling would like to be able to call as many stones/gems as possible paparadscha or Kashmir Blue. Too many paparadscha or Kashmir Blue in the market then a consumer starts to wonder on the definition and pricing. Just my two cents. Regards, pernula |
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| Ha, ha, Valeria101! I won't start with the quality of orient being on a spectrum (really bad, I know!) . . . . Seriously, following up on Jeremy's comments, what I meant to say is, how is the majority definition different? What Strack describes in connection with Tahitian cultured pearls (which sounds to me like several overtones caused by thin film interference, but little or no diffraction?) - would this be considered “orient” by the majority? Basically, several overtones = multi-color (but not necessarily rainbow) shifts = iridescence = orient? Just saw your comment, pernula, welcome, very good point . . . . Perle |
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| Pernula, Welcome from another relative newcomer (“Pearl Advisor” title humbly unearned as yet—but working on it here!). Keep in mind that ‘orient’ is not a factor in commercial pearl grading systems, which focus upon: Luster, size, shape, color. For the purposes of discussion (which members should keep in mind with my posts from time to time…), if iridescence were the key to its understanding, then we’d all be a bit more reverent of mud puddles in parking lots, flies, etc. Not to deny that beauty can indeed be the result (below is a Roman-era lachrymatory bottle we serendipitously obtained quite a number of years ago, its iridescence the natural result of layer separation as a result of slow decay within the original glass). As mentioned very recently on the ‘Pinctada Maculata’ thread, there is an important new grading system in the works for the Cook Islands, since Manihiki atoll has firmly established itself as the second largest producing atoll for black pearls and a resulting need has arisen to better define the production standards there (so they are not perennially lumped in with Tahitians). I’m attempting to get an early read on its direction, and perhaps some further insight into orient as it is perceived there. But as Jeremy has stated, that will simply be their viewpoint. Hope to have a comment soon (not to mention another scoop for Pearl-Guide!). Steve Seattle |
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| Quote:
Sorry, you got me lost... I do not have the Strack book (the last w/o it on the forum !??)... and from the scarce memory of optics at hand, I am not sure I understand how one type of nacre would favor diffraction v.s. interference and how the full range of spectral colors dissociated through either effect end up as different visual effects of orient 'color' etc. On one hand, on another - what is a 'majority' definition of orient? I can only imagine what a long story this is, so I am definitely not asking for the answer here. There is a stack of sources I have stashes and never went through Besides, black lip keshi seem to have just about any color under the sun. What does prompt Strack's comment about Tahitian pearls? Last edited by Valeria101; 06-16-2007 at 07:34 AM. |
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| Steve, Thanks for the welcome. Love your bottles and pearl necklaces posted in another thread. Quote:
I don't know what is the definition of orient or whether iridescence quite describe it. The word orient originate from Latin oriens, rising sun. Some of the pearls in one of Jeremy's baroque very light lavender strand (more like pink) has blue and some gold in it, the colors seem to come from part way inside the pearl and they change as you move the pearls. They do remind me of sunrise, and the three dimensional aspect of the color (coming from within, kind of like seeing through fog) helps give the feeling of mystique. In comparison, an abalone shell, even though it has the same range of colors, seems to have the colors mostly on its surface. They are definitely iridescent and beautiful, but somehow does not give me the feeling of sunrise or draw me in. Regards, Pernula |
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| Quote:
Re the nacre issue, I think (?) what it comes down to is that, because pearls don't form identically, there are differences in their structure that produce different diffraction and interference effects, which is why not all pearls display “orient” (whatever the heck it is!). For those who are interested, more details in Strack (esp. pp. 289-292) and the articles I linked to above. Perle |
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| Quote:
I think the 3-D aspect is getting warm if not hot, and would seem to involve the concept of 'water' mentioned in my earlier post. Steve Seattle |
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| The majority opinion would differ from Strack regarding Tahitian pearls. Although true orient is produced by interference and light diffraction, its result is pearl-surface iridescence, or a play of colors on the surface. This is something that Strack refers to as overtone instead of orient. But the visual effect is that or orient, not overtone. So most in the industry would consider Tahitians to have excellent orient, better than other cultured pearl varieties. But in terms and definitions, there is the academic terminology and industry terminology. The most classic example is CIBJO's new pearl book. Many of the definitions have been influenced by academia that consider much of industry usage incorrect. What you are left with is a new list of terms that often conflict with what is understood in industry. According to CIBJO, the term "tissue nucleation" should not be used, and freshwater keshi do not exist. But can even academia consider this definitive when the same book describes the Gulf of Mexico and the Gulf of California as being the same body of water, and Venezuela bordering the Pacific? Regarding the varying definitions of orient within the different segments of the industry, I do not have a problem with this. It basically comes down to this; they cannot agree. But they don't want to. But does it matter? They are interpreting the same thing differently to suit their own industry, but at the same time using the same definition to describe the rarest and most valuable attribute found in their own production. Either way, to them, it is orient.
__________________ Jeremy Shepherd President and Founder PearlParadise.com, Inc. The PearlParadise.com Channel |
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Would love to see black pearls with good water. Haven't seen it in Tahitians in the jewelry stores around here. Regards, pernula |
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| While I am in the posting mode, I want to give a verbal description of the lightest color pearls in my baroque multicolor strand from Pearl Paradise. They are beautiful in a different way from the apricots and lavenders. The color is kind of pale brownish yellow in some lighting and white in other lighting. If you bring them to a window in the afternoon the pearls do not appear white. Instead they act like concave mirrors, taking on the colors of what they are reflecting. I can see the green lawn, blue sky, and myself reflecting in them. Surrounding the central reflection/mirror is a layer of translucent pale browinsh yellow color with strong hint/overtone?/orient of reddish purple here and there. If the pearls are brought to ten feet from the window they look white with the beautiful reddish purple second color shimmering. They remind me of some pictures in fairy tale books, though I cannot remember which. As beautiful as they are, I can understand why producers might want to treat them. There are small patches of dull spots here and there (on the back, flatter side, usually). Tumbling/Polishing can probably smooth the skin. And if someone had told me I would have 8 or 9 browinsh yellow color pearls I would not have purchase it, not until I saw them and realize how beautiful they are! So in a way I can understand the reasoning for bleaching too. My question to Jeremy, though, is what makes you certain that bleaching does not affect overtone and orient? Did the producers show you some before and after pictures? Thank you for sharing your pearl insights and procuring beautiful pearls at very reasonable prices. Regards, pernula |
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| Even with treatment the strand may have a dull spot. There are two top grades of baroques, and they are called (in Chinese) two side shine, and four side shine. Our entire offering was made up of those two levels. But with treatment (bleaching), the strand you have would not have that color. That is a trademark of untreated pearl lots. There is a color differentiation that melds all the colors together, with more sharp contrast in the color. Bleaching will affect overtone, but will not affect orient, unless the pearls are over processed and the surface is damaged. The maeshori treatment before bleaching and the luster treatment after will actually accentuate the orient for a time. I buy materials both before and after treatment, so I get to see them in both states. I do think the most beautiful are the pearls that are perfect without any treatment whatsoever, but these are very difficult to come by. We are hoping the change this to some extent over the next few months, however. I will be sending Mia from our office to China soon to spend a full week combing through materials for elusive exotics and pearls that need no treatment.
__________________ Jeremy Shepherd President and Founder PearlParadise.com, Inc. The PearlParadise.com Channel Last edited by jshepherd; 06-17-2007 at 05:08 PM. |
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| Hi Pernula and welcome to the forum, I found Your posts very interesting and Your description of the white strand very good, the question of orient and overtone is really very confusing. For myself I think it doesn´t matter that much if some people talk about orient and others of overtone - it should be there if possible because a pearls gets so much more fascinating when shimmering in different pastel colours!
__________________ Inge Jernberg Last edited by jerin; 07-05-2007 at 05:01 AM. |
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