Labortory Services
Diamond Certificate
The ZGL diamond certificate provides a reliable and accurate documentation of a diamond’s identity and grade based on the internationally recognized diamond grading system. Using state-of-the-art equipment, each diamond is analyzed by several gemologists in order to provide the most accurate description of the diamonds quality and characteristics. The carat, color, clarity and cut-commonly known as the 4c’s of each diamond are clearly stated on each diamond certificate. Additional grading characteristics such as finish, girdle, culet and fluorescence are also detailed on the certificate. A diagram of diamond displaying any inclusions is also included on the certificate.
Pair Diamond Certificate
As every experienced gemstone collector knows – there’s no such thing as two perfectly matching diamonds which are identical in all respects. But it’s possible, albeit rare, to find flawless gemstones which are very close to perfect matches. When looking at the similarity of gems, the four C’s of each diamond needs to be compared – that of carat, cut, clarity and color. Ideally a pair will have been cut out of the same rough stone, and by the same cutter. Matching pairs are very rare in nature – particularly since both transparent and fancy color diamonds are so rare to find in the first place. And, the higher the grade of diamond, the harder it will be to find another to match it – finding one perfectly cut, flawless diamond is a rarity, but finding two is an exceedingly rare occurrence – these appearing only every few years. Why ? are Matched Pairs of Diamonds so Desirable? Matching diamond pairs are commonly used to create earrings, combined together in a ring, or used to complement each other in any other type of diamond jewelry. Matched stones can be reused in other settings t side by side, and diamonds of identical value can be conveniently divided as part of inheritances.
Jewelry Certificate
The ZGL Jewelry certificate is used to document jewelry pieces and identify the characteristics of the precious stones featured in each piece. Each ZGL Jewelry certificate features a description of the jewelry piece followed by a statement of the characteristics and grading of the precious stones found in the piece. A statement listing the quantity of gemstones featured in the piece as well as a grading report of the gemstone’s weight, shape, color, clarity, cut, proportions and measurements are featured in the ZGL Jewelry Certificate. In addition, the identification, weight and content of any precious metals found in the piece are described on the certificate. As a further way to identify the jewelry piece, the ZGL Jewelry certificate features an enlarged color photograph of the item. Upon request, the International Gemological Laboratory can easily convert an ZGL Jewelry Certificate into an appraisal certificate.
ZGL Colored Gemstone Certificate
ZGL have equipped ourselves with the most technologically advanced equipment available for the use in the identification and authentication of colored gemstones. ZGL laboratories are equipped with immersion cells, micrometers, spectroscopes, Polari scopes, refractometers, specific gravity liquids, binocular microscopes and spectrophotometers. Each ZGL colored gemstone certificate clearly states whether the stone is natural or synthetic. The certificate identifies the variety of the gemstone, its shape, carat weight, cut, color quality, measurements, transparency factor and major optical characteristics. If the stone had undergone any treatment, this information will be listed on the certificate as well. Upon request, the origin of the gemstone may be determined.ZGL have equipped ourselves with the most technologically advanced equipment available for the use in the identification and authentication of colored gemstones. ZGL laboratories are equipped with immersion cells, micrometers, spectroscopes, Polari scopes, refractometers, specific gravity liquids, binocular microscopes and spectrophotometers. Each ZGL colored gemstone certificate clearly states whether the stone is natural or synthetic. The certificate identifies the variety of the gemstone, its shape, carat weight, cut, color quality, measurements, transparency factor and major optical characteristics. If the stone had undergone any treatment, this information will be listed on the certificate as well. Upon request, the origin of the gemstone may be determined.
ZGL Laser Inscription
Only after the first seven steps of the grading process have been completed is the diamond sent for laser inscription. If a Diamond Précis was ordered for the diamond, it will have the identification number laser-inscribed on its girdle. The inscription number is the same as the ID number on the diamond’s certificate. For a small additional fee, diamonds receiving an ZGL Diamond Grading certificate may also have their ID number laser inscribed on the its girdle. Additionally, all diamonds may receive an inscription of a specific brand or company name or a personal message for the customer. (This service is considered as extra service and not include in the ZGL basic grading service pack.)