Both GIA (Gemmological Institute of America) and HRD (Hoge Raad voor Diamant or The Diamond high Council) have the good intentions to comment on the diamonds as accurately as possibly. Although their intentions are honourable they, not always, have the best gemmologists in their employ. Therefore, as a buyer, it is always advisable to get the International Certificates verified by top gemmologist(s) in their own country. A few of our Australian Laboratories and Gemmologists have very good intentions, make a correct disclosure and are not influenced by large merchants passing them constant business.
Both GIA AND HRD comment on the shape, measurement, weight, clarity grade, colour grade, fluorescence, total depth, table size, descriptive term on the girdle and the culet size.
GIA does not comment on the Proportion whereas HRD does. In doing so, it gives the girdle size, crown height, and the pavilion depth. The sum of all these is the total depth of the diamond expressed in the % of the average diameter of a Round Brilliant Cut Diamond.
The terminology used by GIA in commenting on the Finish of the Diamond is:
Excellent, Very Good, Good, Fair and Poor.
HRD, on the other hand, in grading the proportion uses the terms Very Good, Good and Unusual (meaning unusually negative). The Finish is graded as Very Good, Good, Medium and Poor.
Both laboratories also Laser Inscribe the certificate number on the girdle of the diamond. It is advisable to get this done, at an extra cost, for immediate protection and for the protection in the future.
HRD also seals the diamond in a plastic container; however, it is always advisable to get the diamond laser inscribed, as it is better to view the diamond without the plastic container.
GIA grades diamonds using the GIA rules. HRD uses IDC rules. Most Australian Laboratories, with Australian Gemmologists, use the GIA and CIBJO rules of grading. It is our opinion that whatever grading or a mix of grading that one may use, the reporting on the diamond must be correct or reasonably correct. Remember grading of a gem is done in order to obtain a monetary value.
Diamond Certification Laboratory of Australia (DCLA) does not comment on the finish on the diamond. The comment on the finish on the diamond is an important parameter affecting the value of the gem. The IDC rules on “Cut refers to the overall description of the proportions on the one hand and the finish of the diamond on the other hand. The proportions are determinative for the brilliancy and the fire of the diamond, while the finish represents the extent to which deviations occur from the symmetry and other characteristics of cut. The description of the cut on a certificate is split into a separate description of the proportion and of the finish.” HRD.
It is our opinion that a buyer should buy the most brilliant diamond, with the best possible colour and then the clarity within the weight restricted by the buyer’s budget. The diamond must be locally certified and if it is Internationally Certified then it ought to be rechecked by a Local Laboratory where one of the officers is an Australian Gemmologist who is FGAA (Fellow of The Gemmological Association of Australia and a member of JATVC (Jewellery and Allied Trades Valuers Council) or NCJV (National Council of Jewellery Valuers)
Most local laboratories are able to give you an indication of the retail market value as well.
Over the past ten years we have done research into finding the top 10 Gemmologist and Laboratories in Australia. If you wish to use the services of these top Gemmologists in your city please contact us by email, facsimile or phone.
Finally, one must remember that in order to value a diamond or a gem it must be graded first. Our Australian Laboratories are able to do this professionally and efficiently. There have been a number of occasions when the grading of GIA and HRD has been in gross error. American Gem Society states in its certificate “This document is not a warranty, guarantee or appraisal of value.” In fact we doubt if the consumer is protected under the Australian Consumer Laws if their reliance is placed on the grading of the foreign laboratory only. Even if they are then the litigation has to be done in a foreign country, which can be an expensive process.
Both GIA AND HRD comment on the shape, measurement, weight, clarity grade, colour grade, fluorescence, total depth, table size, descriptive term on the girdle and the culet size.
GIA does not comment on the Proportion whereas HRD does. In doing so, it gives the girdle size, crown height, and the pavilion depth. The sum of all these is the total depth of the diamond expressed in the % of the average diameter of a Round Brilliant Cut Diamond.
The terminology used by GIA in commenting on the Finish of the Diamond is:
Excellent, Very Good, Good, Fair and Poor.
HRD, on the other hand, in grading the proportion uses the terms Very Good, Good and Unusual (meaning unusually negative). The Finish is graded as Very Good, Good, Medium and Poor.
Both laboratories also Laser Inscribe the certificate number on the girdle of the diamond. It is advisable to get this done, at an extra cost, for immediate protection and for the protection in the future.
HRD also seals the diamond in a plastic container; however, it is always advisable to get the diamond laser inscribed, as it is better to view the diamond without the plastic container.
GIA grades diamonds using the GIA rules. HRD uses IDC rules. Most Australian Laboratories, with Australian Gemmologists, use the GIA and CIBJO rules of grading. It is our opinion that whatever grading or a mix of grading that one may use, the reporting on the diamond must be correct or reasonably correct. Remember grading of a gem is done in order to obtain a monetary value.
Diamond Certification Laboratory of Australia (DCLA) does not comment on the finish on the diamond. The comment on the finish on the diamond is an important parameter affecting the value of the gem. The IDC rules on “Cut refers to the overall description of the proportions on the one hand and the finish of the diamond on the other hand. The proportions are determinative for the brilliancy and the fire of the diamond, while the finish represents the extent to which deviations occur from the symmetry and other characteristics of cut. The description of the cut on a certificate is split into a separate description of the proportion and of the finish.” HRD.
It is our opinion that a buyer should buy the most brilliant diamond, with the best possible colour and then the clarity within the weight restricted by the buyer’s budget. The diamond must be locally certified and if it is Internationally Certified then it ought to be rechecked by a Local Laboratory where one of the officers is an Australian Gemmologist who is FGAA (Fellow of The Gemmological Association of Australia and a member of JATVC (Jewellery and Allied Trades Valuers Council) or NCJV (National Council of Jewellery Valuers)
Most local laboratories are able to give you an indication of the retail market value as well.
Over the past ten years we have done research into finding the top 10 Gemmologist and Laboratories in Australia. If you wish to use the services of these top Gemmologists in your city please contact us by email, facsimile or phone.
Finally, one must remember that in order to value a diamond or a gem it must be graded first. Our Australian Laboratories are able to do this professionally and efficiently. There have been a number of occasions when the grading of GIA and HRD has been in gross error. American Gem Society states in its certificate “This document is not a warranty, guarantee or appraisal of value.” In fact we doubt if the consumer is protected under the Australian Consumer Laws if their reliance is placed on the grading of the foreign laboratory only. Even if they are then the litigation has to be done in a foreign country, which can be an expensive process.
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