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Sndgems jewelry guides are easy to use, interesting and helpful guide to buying jewelry onle. Our jewelry guides are indispensable guide to judging jewelry characterstics, distinguishing genuine from imitation, making wise choices, useful to all type of consumers, from professional jewelry to online searchers. Our diamond guides help everyone in viewing diamonds as gemologists, diamond experts, diamond dealers, experienced lapidaries, diamond buyers and online customers. Our diamond guides dissects each aspect of diamond value in detail with a wealth of diamond grading information. Our gemstone guides help everyone in viewing colored gemstones as gemologists, gem dealers, experienced lapidaries, gem buyers and online customers. Our gemstone guides dissects each aspect of ruby, sapphire, ruby value in detail with a wealth of gemstone grading information. Our guides offers step-by-step instructions for how to examine and judge the quality and craftsmanship and materials even if you dont know anything about jewelry. If you're thinking of buying jewelry online this guide is a best place to start. Our guides will help you to know about jewelry details such as finishes, settings, flaws and fakes. Our guides cover diamonds, gemstones, jewelry craftsmanship, treatments, diamond and gems sources, appraisals. There is something for everyone. Identification of Synthetic or Fake Imitation Diamonds from Genuine Diamonds Buying Guides Diamond Experts can sometimes not be able distingiosh between imitation and natural diamonds. The high price of gem-grade diamonds has created a large demand for materials with similar gemological characteristics, known as diamond simulants or imitations. Simulants are distinct from synthetic diamond, which unlike simulants is actual diamond, and therefore has the same material properties as natural diamond. Enhanced diamonds are also excluded from this definition. A diamond simulant may be artificial, natural, or in some cases a combination thereof. While their material properties depart markedly from those of diamond, simulants have certain desired characteristics—such as dispersion and hardness—which lend themselves to imitation. Trained gemologists with appropriate equipment are able to distinguish natural and synthetic diamonds from all diamond simulants, primarily by visual inspection. The most common diamond simulants are high-leaded glass (i.e., rhinestones) and cubic zirconia (CZ), both artificial materials. A number of other artificial materials, such as strontium titanate and synthetic rutile have been developed since the mid 1950s, but these are no longer in common use. Introduced at the end of the 20th century, the lab grown product moissanite has gained popularity as an alternative to diamond. In order to be considered for use as a diamond simulant, a material must possess certain diamond-like properties. The most advanced artificial simulants have properties which closely approach diamond, but all simulants have one or more features that clearly and (for those familiar with diamond) easily differentiate them from diamond. To a gemologist, the most important of differential properties are those that foster non-destructive testing, and most of these are visual in nature. Non-destructive testing is preferred because most suspected diamonds are already cut into gemstones and set in jewelry, and if a destructive test (which mostly relies on the relative fragility and softness of non-diamonds) fails it may damage the simulant—this is not an acceptable outcome for most jewelry owners, as even if a stone is not a diamond it may still be of value. DIAMOND IMITATIONS: There are three common simulants of diamonds. These are cubic zirconia, synthetic moissanite and artificial glass. Here we a look at the simulants and their features that distinguishes them from diamonds See-through Test Look carefully at the stone face up and can you see through the stone. If you can see through then most probably it is an imitation. Put the stone on a newspaper and if you can read the letters then most probably it is an imitation. Tilt Test Tilt the stone against a dark background and try to see a dak fan shaped area in the stone then most probably it is an imitation. This test is similar to see through but is more for mounted stones. Rainbow Colors Test View the stone under a light and see how strong the flashes of rainbow colors in comparison to a real diamond under the same light. If the stone shows a lot more of rainbow of colors the stone may be synthetic rutile, strontium titanate or synthetic moissanite. If the rainbow of colors is less then the stone may be another imitation of diamond with a large table and a thin crown. Cubic Zirconia also displays more rainbow of colors than diamond and should be viewed under fluoroscent light. Closed Back Test If the stone is already set in a jewelry look at the back of the setting and if the stones bottom is blocked from view or enclosed in the settings metal the chances are the stone is synthetic or inferior quality. Price Test If the stone is being sold at very low price then most probably it is an imitation. Thermal Conduction Test An easy, quick and accurate way of finding if a stone is a diamond imitation is by using GIA GEM pocket thermal tester which measures the heat conductivity of the stone. A metal probe or heat pen is pressed on the facet of the stone. Then the tester will indicate if it is a diamond or a imitation. Moissanite was launched in 1998 and has same thermal conductivity as the diamond so this tester will not be able to detect between diamond and a moissanite. There are other ways to help identify it - double facet test, specific gravity, reflecyivity, moissanite tester. Sndgems.com diamond jewelry comes with an complimantary GIA GEM tester. Girdle Test With a 10X Magnifier examine the girdle of the stone. If the girdle has been carefully formed then it is a diamond or a moissanite. All other diamond imitations don't have a well formed girdle. Double Facet Test This is a important test in detecting moissanite. If you see double facets or double table reflection then it is not a diamond. Diamond refracts light in a single direction so that its facets appear as single lines. Synthetic moissanite and synthetic rutile are doubly refractive and display doubling. To detect doubling tilt the stone and look at it from an angle. Focusing and defocusing a microscope will help you in detecting doubling. GlassTest Glass has gas bubbles, rounded facet edges, concave facets and surfaces, swirl lines or formations and uneven surfaces. Other Tests Diamonds when looked under magnification will show crystals, graining, laser drill holes, naturals and trigons. Stimulants have gas bubbles and Synthetic Moissanite have whitish needles, surface pits, polish lines and rounded facets and facet junctions. Diamond has high transparency while stinulants will look hazy. Reflectometer measures relective capacity of a stone. Diamond and Stimulants have different unique relective capacity which can be measured by a reflectometer called Diamond Eye. Same size diamonds weigh less than imitations except glass. Diamonds have a lower specific gravity of 3.52 than stimulants and when immersed in a heavy liquid with specific gravity of 3.32, diamond will sink while stimulants and moissanite will float. X-ray - Diamond are extremely transparent and show blue fluoroscence to x-rays while stimulants arn't. Spectroscope: It measures light absorbed by a stone or a diamonds. Diamonds have characterstic readings and can easily be dtected from stimulants. Moissanite Tester - After using thermal diamond tester use Moissanite Tester called C3 and it measures the absorption or reflection of near ultraviolet portion of the spectrum, Colored Diamonds cannot be easily diffeentiated with this tester. Following are some of the properties by which diamond and its simulants can be compared and contrasted. WHAT TO LOOK OUT FOR: DIAMONDS naked eye and 10x loupe Diamonds should always have sharp facet edges due to its hardness (facets are the flat polished surfaces on a cut gemstone) A Bright lustre should be seen (lustre is the way light interacts with the surface, diamond has a adamantine lustre) A Good polish should be visible on good quality diamonds Diamonds are singly refractive Natural diamonds will always contain natural inclusions. Inclusions are a great tool for identifying diamonds from their simulants. Natural diamond inclusions include: Clouds, feathers, needles, pinpoints, crystals, cleavage, bearding, internal graining and dark crystal inclusions. These all aid with the identification of natural diamonds. The finishing on the girdle of a diamond can be used as an indicator for diamonds. A girdle is the a edge around the diamond where the top (crown) and bottom (pavillion) of the stone meet. A diamond girdle may have a sugared appearance otherwise known as a ground girdle, it may also be bruted, polished or faceted. Grinding lines should NOT be seen on the girdle of a diamond , if grinding lines are visible then its most likely a simulant Bearding may be seen on diamonds, these are short and very fine cracks around the girdle Finally, if there is a large modern stone with good colour and clarity but a poor cut it should raise suspicions MOISSANITE naked eye and 10x loupe Moissanite is doubly refractive. This can be used to aid identification because diamond is singly refractive. A doubly refractive stone will show doubling of facets or inclusions which can be seen with a 10x loupe however a singly refractive stone will not show this. Moissanite will have a slightly green tinge Parallel needle like inclusion are sometimes visible Beware with moissanite because it is also a very hard material so facets edges will be sharp. The best way to identify moissanite is through double refraction Moissanite shows a very high dispersion (this is the stone ability to show different colours when due to the splitting of white light into the colours of a the visible spectrum) CUBIC ZIRCONIA naked eye and 10x loupe
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