Impact of FluorescenceFluorescence, properly called photo-luminescence, is caused by a trace amount of the element boron found in the diamond. It is activated by UV (ultra-violet) light. Fluorescence in a diamond is described on GIA certificate as None, Faint, Medium, Strong, and Very Strong Blue. Other colors of fluorescence do occur, yellow, orange and white for example (try to avoid them), but it is the blue we are most commonly involved with. In the old days people used to come looking for the perfect "blue-white" diamond. The blue referred to the fluorescence and the white to the diamonds body color. About 10 years ago someone (some type of rumor spread from Korea) decided blue was not a good color and suddenly diamonds exhibiting fluorescence became out of fashion. In one of the issues of Gems and Gemology (put out by GIA) GIA states that typically fluorescence is a plus in diamonds. Also there was a show on PBS where they were talking about how beautiful and rare fluorescence is in a diamond. Who knows, in a few years fluorescent diamonds may be back in fashion and will demand a premium. My suggestion is this. If you are offered a diamond that exhibits fluorescence be sure you examine it under ALL light conditions. That especially includes direct sunlight and a jewelers black light. Faint and Medium fluorescence I have normally found to have, if anything, a positive effect, causing the diamond to have a little "extra life" in the sunlight. If you are dealing with a diamond of H color or lower fluorescence is normally a plus, and will increase the diamonds beauty and desirability. So to sum up, be sure to examine any diamond with fluorescence under all light forms and make up YOUR mind for YOURSELF, as to whether it is a plus or minus.
Following is an article published in Gems & Gemology by William E. Boyajian, President of Gemological Institute of America (GIA). “The effect of ultraviolet fluorescence on diamond appearance has been hotly debated at least the past decade. Opinions of even the most experienced trades people vary widely. With great conviction, some say that blue fluorescence of different strengths typically enhances a diamond’s overall appearance. Others, as convincingly, say that it has a negative effect. To address this controversy, researchers at the GIA Gem Trade Laboratory conducted an experiment on the effects of long-wave ultraviolet radiation on the color appearance and transparency of gem diamonds. Their results are reported in this issue. This study challenges the perception held by many in the trade that UV fluorescence generally has a negative effect on the overall appearance of a diamond. In fact, the results support the age-old belief that strong or even very strong blue fluorescence can improve appearance rather than detract from it, especially in diamonds with faint yellow body color. This result is consistent with the slightly higher “asking?prices reported for these stones. While the apparent benefits of blue fluorescence are less obvious in colorless to very near-colorless diamonds, they still were evident in the study. This should bring into question the trade’s lower “bid?prices for moderate to highly fluorescent diamonds in the better colors. It also makes us question the source of the present controversy surrounding fluorescent diamonds. It may be the result of trade members?misunderstanding of the complexity of the issue, or the extreme price sensitivity in the highest color grades (where there are fewer stones and distinctions are more subtle). Or it may be the fact that it is simply easier to move good without the encumbrance of a reported fluorescence. To some extent, this type of research project is unusual in gemology, in that human observation rather than instrumental analysis is the key tool. Yet evaluation of this human element is just the kind of important research that is needed to help resolve misunderstandings and false perceptions among members of the trade and even the consuming public. Gemological research involves not only the physical, optical, and chemical nature of gems, but also the visual assessment of stones in buying and selling situations. GIA will never alter its course of promoting the scientific examination of gem materials to seek knowledge and understanding, but we also want to encourage more research studies that address important trade concerns. Thus, we believe that the diamond fluorescence article is as significant a contribution to gemology as the synthetic moissanite and synthetic emerald articles also featured in this issue. After all, the science of gemology is not just R.I.’s and S.G.’s, or even sophisticated chemical and spectral analysis. It is also about dispelling (or, in some cases confirming) beliefs that have been perpetuated over the years, and about separating bias and tradition from reality in the gem industry.?
Following is a GIA letter that was sent to interested jewelers who wanted an official statement from GIA concerning Blue fluorescence: “To Whom It May Concern: The following comments are in response to many inquiries regarding the characteristic of ultra violet fluorescence on out diamond grading reports. I trust the following will be of interest to you. Objection to fluorescent diamond is probably based upon their early association with off color diamonds. Our grading experience, however, has shown that diamonds of any color on the GIA scale, may be fluorescent. We test for ultra-violet fluorescence in a darkened laboratory environment using a concentrated source of ultra violet light. Although the presence of faint or moderate fluorescence has no affect on the color appearance of a diamond, it is nevertheless recorded on our reports as an identifying characteristic of a particular diamond. It is only when ultra violet fluorescence is strong or very strong that it has any significant impact on the color appearance of a diamond in daylight. In most cases, fluorescence enhances the daylight color appearance of a diamond. I hope this satisfactorily answers your question. Very truly yours, GIA Gem Trade Laboratory, Inc. Bert Krashes Vice President, Director, Diamond Grading Services?/P>
Following is an article published on page 20 of National Jeweler magazine: New York ?As the saying goes, when two diamond dealers get together, you get three opinions. This is especially true on blue fluorescence. Some say that strong blue fluorescence ?which can only be seen when a diamond in exposed to ultra-violet radiation or high-energy X-ray ?makes stones prettier and more valuable. Others dislike fluorescence and say it makes a stone worth less money. Some split the difference and say it helps in some stones and not in others. Hoping to shed a little ultra-violet light on the subject, the Gemological Institute of America (GIA) recently conducted a study on the effect of blue florescence on the appearance of diamonds, for the winter issue of its publication Gems and Gemology. The study’s conclusion: blue fluorescent generally either helps, or had no effect on a stone’s appearance ?and, chances are, most consumers don’t notice much anyway. Tom Moses, GIA’s director of identification services and one of the study’s authors, said the GIA has always been puzzled why something which generally is not visible to the naked eye should make a difference in the price of the diamond. The GIA concludes that: * Most of the none gemologically trained “average observers?the GIA study brought in could not distinguish between stones with strong blue fluorescence and stones without it ?leading the GIA to conclude most consumers would feel the same. They felt it had no impact on color appearance or transparency. ?Some of the more experienced observers ?including veteran GIA graders ?thought that diamonds with strong blue fluorescence had a better appearance when viewed from table up ?the way most diamonds are displayed ?but there was no difference when viewed table-down. Yet, even the experienced observers did not consistently agree on how much impact fluorescence has. ?* Most observers saw no relationship between fluorescence and transparency. Moses noted the study only covered colorless to faint yellow diamonds, but said the GIA may one day investigate strong blue fluorescence’s effect on fancy-colored diamonds.
Synthetic Moissanite: Diamond look-alike synthetic moissanite is the lab-created version of silicon carbide, a natural material first discovered in 1893. The substance was found in a meteorite by French Nobel price-winning chemist Dr. Henri Moissan, for whom the natural stone was named in 1905. Today, natural sources are rare. Synthetic moissanite is currently being produced by Cree Research and marketed by the company C3, both based in Research Triangle Park, N.C. Description: Moissanite was originally mistaken for diamond, because the stone shares many of diamond’s optical properties. Moissanite’s refractive index and dispersion rant higher than diamond, giving the synthetic stone the fire and brilliancy of the real thing. However, moissanite’s 3.21 specific gravity is lower than diamond’s 3.52. Lab-created moissanite is the second hardest gemstone next to diamond, with a 9.25 rating on the Moh’s hardness scale. Moissanite outranks even the toughest of corundum in terms of durability. Moissanite is the carbon-based material that has some thermal conductivity. Detection: Moissanite cannot be detected with traditional thermal probes, because the synthetic’s properties are similar to diamond. Therefore, a little more detective work is required to identify moissanite. The synthetic material is doubly refractive, which can usually be spotted using a 10X loupe. Most samples have a grayish or light yellowish appearance when put side by side with colorless diamond. Moissanite floats in specific gravity liquid 3.31, while diamond sinks. Several different moissanite detectors are available on today’s market, including a simple and inexpensive “scratch test.?
Oved Announces New Clarity Enhancement Process(Rapaport?3 April, 2000) New York-based Oved Diamond Company announced the successful development of a new diamond clarity enhancement technique. The company is one of a number of companies offering clarity enhancements. “The biggest problem with clarity enhancement used to be the jeweler’s torch. When subjected to it, the treatments would always fail. This new process eliminates that problem because our new treatment can withstand a jeweler’s torch for any normal bench work,?said co-owner Jonathan Oved. In the past few years Oved has placed great focus on research and development and it has clearly paid off. After a year and a half of research and testing on thousands of stones, the company’s resident chemical engineer discovered a method of ensuring much greater durability for the treatment. The new treatment is being called “XL21?and diamonds treated with it will cost the same as those previously treated, which, according to Oved, is 20 percent less than competing treated diamonds. According to Oved, the treatment is currently successful in 75 percent of all stones processed, but the company is aiming for the coveted 100 percent success rate. The different nature of each individual imperfection accounts for the deficit. The company does not intend to offer the treatment to the trade as a service, but it will be used exclusively for diamonds sold by Oved. The firm is also offering retailers who bought stones treated with the old process, the opportunity of having those stones treated with the XL21 process. The company will be marketing the stones as a brand and each enhanced diamond will have the Oved logo inscribed not on the girdle of the stone like most brands, but on the bezel facet. The bezel facet was chosen because many settings obscure the girdle. The brand requires a 10x magnification to see it. Pacific Technologies is doing the laser inscription for the enhanced diamonds. According to Oved, the Gemological Institute of America has been testing the stones and preliminary results are “positive.?In other words, the stones are apparently withstanding “normal bench work.?There is reportedly a yellow to orange flash indication of the fill but the refractive index on the fill is “almost the same as the diamond.? “The GIA does not certify treated diamonds but maybe with this more durable treatment they will think about it a bit more?says Oved. Oved is treating twenty pointer stones and up and is testing the consumer market through the release of some stones to an initial five retailers, one of which is Borsheim’s in Nebraska. The company is also creating a website dealing with clarity enhanced diamonds which will act purely to educate consumers about the issue. Given its greater durability Oved believes that the new process will change the market. ?Copyright 1982-2000 by Martin Rapaport. All rights reserved. While the information presented is from sources we believe reliable, we do not guarantee the accuracy or validity of any information presented by Rapaport or the views expressed by users of our internet service.
From Professional Jewelers article on GE-POL treated diamondsApril 25, 2000 Labs Identify GE/POL Traits De Beers scientists in England and South Africa discovered a quantifiable way to identify GE/POL diamonds using spectroscopic techniques to find nitrogen vacancy centers in the treated diamonds. The research was published this week in the Spring 2000 issue of Gems & Gemology, the Gemological Institute of Americas quarterly journal. Separately, the SSEF Gemmological Laboratory, Basel, Switzerland, announced a new routine service to identify GE/POL treated diamonds based on its study of treated and untreated diamonds, which will be published this spring in European gemological journals. The SSEF study also depends on the identification of nitrogen vacancy centers. The De Beers study examined 39 treated and 30 non-treated Type IIa diamonds. The study reported spectroscopic observation of luminescence peaks using laser excitation of cryogenically cooled diamonds. (Cooling, usually with liquid nitrogen, helps define absorption patterns). Specifically, De Beers scientists observed excitation peaks at 575 and 637 nanometers in most of the GE/POL diamonds studied. The peaks result from nitrogen vacancy centers, which are a single nitrogen atom in a vacancy. Normally, Type IIa diamonds have little or no nitrogen; the presence of nitrogen in the GE/POL diamonds is what makes them treatable. De Beers is working with several laboratories to develop a practical way to apply its research. Raman spectrometers, used in combination with cooled diamonds and laser excitation, could record the differences and make determinations. According to GIA, the authors say a majority of GE/POL diamonds will be identifiable when their spectral features are combined with the GE/POL characteristics observed by microscope in an earlier GIA study (Fall 1999 Gems & Gemology). De Beers research into the GE/POL process is part of its Gem Defensive Program. The SSEF Web site says its identification is essentially based on laser-induced fluorescence spectroscopy performed on a Raman system at liquid nitrogen temperature. SSEF says it observed a luminescence pattern that proves the presence of a small number of nitrogen vacancy centers in all the GE/POL treated diamonds it studied. None of the non-treated stones SSEF studied showed the nitrogen vacancy centers. On a practical level, identification of GE/POL diamonds using these kinds of tests will not be done by retailers, since the equipment needed to do the job is beyond the reach of conventional gemology and prohibitively expensive. GE's reaction to the latest news? "The study and tests are encouraging," says Dr. Thomas Anthony, the GE staff physicist who developed the GE/POL treatment. "The test is reliable for the lower colors of diamonds J-Z stones because they contain nitrogen. But it's not reliable for higher colors or clean diamonds." [Note: For diamonds without nitrogen, examination of inclusions and how they react under HPHT may be needed. In this case, a D-flawless GE/POL diamond would not be as easily detected.] "In terms of dollar value, on a piece-by-piece basis, 90% of the stones are still undetectable," says Anthony. He says GE researchers are studying detection methods also, but that a 100% solution has eluded them so far. For copies of the Spring 2000 Gems & Gemology, call (800) 421-7250, ext. 7142; e-mail firstname.lastname@example.org, or go to www.gia.edu/gandg/index.cfm. For more information on the SSEF labs study, go to www.ssef.ch. Click on Infos, then News.) - by Robert Weldon, G.G.
What are Conflict Diamonds? Conflict diamonds are diamonds illegally traded to fund conflict in war-torn areas, particularly in central and western Africa. The United Nations (UN) defines conflict diamonds as "...diamonds that originate from areas controlled by forces or factions opposed to legitimate and internationally recognized governments, and are used to fund military action in opposition to those governments, or in contravention of the decisions of the Security Council." These diamonds are sometimes referred to as "blood diamonds."
Conflict diamonds captured the world's attention during the extremely brutal conflict in Sierra Leone in the late 1990s. During this time, it is estimated that conflict diamonds represented approximately 4% of the world's diamond production. Illicit rough diamonds have also been used by rebels to fund conflicts in Angola, Liberia, Ivory Coast, the Democratic Republic of Congo and the Republic of Congo (also known as Congo Brazzaville).
Today, the flow of conflict diamonds has been reduced to considerably less than 1%. There are three diamond producing countries that account for this small percentage. Firstly, the Republic of Congo has been suspended from participation in the Kimberley Process owing to areas of non-compliance. Secondly, Liberia and the Ivory Coast are under United Nations Security Council Resolutions to prohibit the extraction and trading of diamonds. Despite both the Republic of Congo and Liberia benefiting from internationally recognized peace agreements, diamonds from these countries may be referred to as "conflict diamonds".
Eliminating Conflict Diamonds
In July 2000, the global diamond industry made clear to the international community its zero tolerance policy towards conflict diamonds. Dedicated to eradicating the trade in conflict diamonds, it worked closely with the United Nations, governments and non-governmental organizations (NGOs) such as Global Witness and Partnership Africa Canada to create the Kimberley Process Certification System. This system was formally adopted in 2003 and guards against conflict diamonds entering the legitimate diamond supply chain. The diamond industry also adopted a voluntary System of Warranties to assure consumers that their diamonds are from sources free of conflict. Today 71 governments have enshrined into their national law the Kimberley Process Certification System, and now more than 99% of the world's diamonds are from conflict free sources. However, even one conflict diamond is one too many. The diamond industry continues to work with governments, NGOs and the UN to strengthen the Kimberley Process and the System of Warranties. While diamonds have been used to fund conflict, the problem is not the diamonds themselves but the rebels who exploit diamonds (along with other natural resources) to achieve their illicit goals. The vast majority of diamonds come from countries at peace. These countries have been able to invest the revenue from diamonds into the development of infrastructure, schools and hospitals for the good of the communities in which diamonds are found. These countries include Australia, Botswana, Canada, Namibia, Russia, South Africa and Tanzania.
Today, more than 99% of the world's diamonds are now from conflict free sources and are officially traded under the UN mandated Kimberley Process.
"Diamonds are a unique resource, evoking beauty and eternal love. In recent years, pictures of maimed children have threatened to overwhelm these traditional positive images, when rebel groups in Africa used diamonds to finance their wars and unspeakable brutalities against civilian populations. Aroused by these conflicts, the international community mobilized to ensure people living in countries with abundant diamond deposits receive the benefits of their patrimony. Outraged in the late 1990's that proceeds from diamond sales financed arms purchases and prolonged insurrections, in Sierra Leone and Angola, which were some of the most brutal of the past decade, the international community acted. By 2003 the international community through the participants in the Kimberley Process, bringing together industry, governments and civil society, mobilized governments to ban trade in rough diamonds funding African conflicts. Called the "Kimberley Process Certification Scheme" the ban ended those African conflicts financed by "blood" diamonds. Based on the respect for human dignity, the negotiators found the following common interests to win support for an international ban on trade in rough diamonds used to finance war and rebellion:
· First, in memory of those who died in Sierra Leone, in Angola, in the Democratic Republic of the Congo and other African countries in conflicts fueled by rough “Conflict’ Diamonds;”
· Second, to end the killing in on-going conflicts in Africa;
· Third, to save the children of Africa whose lives would be threatened by future conflicts fueled by conflict diamonds;
· Fourth, to ensure those countries which depend on diamonds for their development and economic well-being will benefit from their patrimony; and
· Fifth, to assure consumers the diamonds they wish to enjoy are without the taint of conflict.
Through the worldwide implementation of the Kimberley Process Certification Scheme we have begun to fulfill the international community's obligation to those who have suffered in Africa's wars by banning the trade in conflict diamonds. We have eliminated conflict diamond financing in Sierra Leone and are committed to bring the proceeds from the diamond trade to benefit the people of Sierra Leone, Angola and Liberia as well as all other diamond producing countries such as Botswana to help themselves support economic development of their countries." - Ambassador J.D. Bindenagel, Former U.S. Special Negotiator for Conflict Diamonds
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