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A question about polish


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I recently bought a Diamond and I had ab appraisal done on the stone


I am not happy with the fact that the stone appraised with a Polish of Fair


I am wondering if there is a way to incress the Polish of a Diamond.


its something that i know my girl friend more than likely wont notice or really worrie about but it will bug me so i am more than likely going to get a different stone.


but I would still like to know if the polish of a diamond is something that can be changed?

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Hey TV,


The answer is sometimes yes and sometimes no.


When a cutter is applying the final step of "polish" there are many issues that can prevent a diamond from receiving the high lustre of AGS "ideal" or GIA "excellent" polish. One of the main preventing criteria is that of graining. When a diamond is being polished against the grain, this causes more friction/grit and increases the chances for polish flaws such as polish lines/grooves causing the lustre to decrease. Another could be imperfections that reach the surface. It could be a number of things but if it has polish considered to be "fair" the chances that it'll get better are not good.


While I would consider proportions and symmetry more important that polish, all of these metrics help contribute to the value of the diamond.

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It is quite rare to see "Fair" polish on certed diamonds, today; certainly not on either GIA or AGS certs.


Internal QC by the manufacturer will flag 'fair polish" before the diamond is ever submitted to the lab for certification. Diamonds submitted for Certs will already have, as a minimum, "Good" polish.


In diamonds that do not have issues such as graining, nats, cleavages, etc. which make it difficult to polish out to 100%, a fair polish area may be the result of a burn mark due to excessive pressure placed by the cutter onto the dop as it is on the wheel or his wheel not being coated with high quality diamond powder/oil that leaves a film on the diamond planes surface and junction lines. These can be easily corrrected and a "fair" polish area converted to "Good" polish or even better.


Diamonds that can only achieve "Fair" polish are invariably I-1 and lower clarity grades that are not sent for certification and are sold as commercial lots and used for promotional jewelry.

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