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Fracture filling correct diamonds have eye visible chips or cracks. For instance, the diamond on the right is a perfect candidate for fracture filling.
During the clarity enhancement process a microscopic amount of material is inserted into the feather or crack (imperfection). This material has the same optical properties as the diamond. When light travels from one medium to another, it either changes its course or reflects in a different direction. When light attempts to pass through a non-enhanced diamond that has an imperfection, the light hits the imperfection and reflects off in any number of directions. That is why we see the imperfection, and the diamond does not appear to be eye clean. With a fracture filled diamond, the light passes through the fracture-filled imperfection because the material used for the enhancement has the same optical characteristics as the diamond.
How to detect fracture filling
Fracture filling clears up the imperfections very well. The only way to detect fracture filling is under the microscope. We have to observe the diamond face down (from the pavilion). Fracture filling leaves a faint to strong neon colour in the stone. The faint purple flashes in the following pictures indicate that the diamond has been fracture filled:
Can the filling in a fracture filled diamond come out?
It is possible for the filling in a fracture filled diamond to come out. However, it is not likely. The Gemological Institute of America (GIA) has put these stones through rigorous of tests. They found only 3 things that could cause the filling to come out.
Therefore, in reality, only a jewellers torch and a jewellers boiling acid are all you need to beware of. If you ever need to get your ring reworked by a jeweller, be sure to tell him that your diamond is clarity enhanced because it is likely that they will be using a torch and boiling acid to work on the ring. Plus, do not send the diamond for recutting.
As fracture filling may fall out, GIA (as with all major diamond testing labs) does not certify fracture filled diamonds.
The Yehuda Diamond Company, which invented the fracture filling process, guarantees that the diamond will never become "unfilled" or "unenhanced" for the life of the stone. If you If you do buy a clarity enhanced diamond you should get this little guarantee (a wallet sized plastic card) accompanying your purchase. Present this card to a jeweler who will be doing work on your ring, should you need any done and they should know what to do.
Unfortunately, the Yehuda Diamond Company is not represented in Singapore.
So, if you have a fracture filled diamond that has been "unfilled",
you will have to find a way to send it back to the closest representative
How would I know if the diamond has been fracture filled?
Unless you are trained to look at diamonds with the microscope, chances are, you will not be able to find out unless your jeweller tells you so. Unfortunately, not all jewellers are able to detect fracture filling themselves. Even if they do know, they may not tell you. Therefore, it is important to buy diamonds only from reputable and experienced jewellers.
Does Fracture Filling reduce the price of a diamond?
Fracture filling does not reduce the price of a diamond. However, it does not increase it significantly either. For instance, you have a 1.28ct G Colour I2 diamond, you should pay the price of a 1.28ct G Colour I2 diamond, even if the diamond looks like a VS2 after all the cracks and chips have been filled up.
Therefore, it is important to find a honest jeweller because it is likely that a jeweller may sell you the diamond at the price of a VS2 diamond, and you would not know any better. Jewellers should tell you that the diamond is enhanced BEFORE he sells the diamond to you.
Should I consider a fracture filled diamond for my Proposal Ring?
However, I am going to advice you against getting a fracture filled diamond in Singapore. Mainly because most jewellers here, who are either trained in Hong Kong or Malaysia, have not seen such diamonds. It is likely that they would loosen the filling when they are setting the diamond. If you should like to alter the ring in any way, the jeweller may also apply the torch too close to the diamond and loosen the filling.
In addition, if the filling comes out, you will probably have to send it back to the Yehuda Diamond Company in the US. You would probably have to bear the cost and the risk (or insurance) of shipping it back to Yehuda.
How do I ensure that my diamond is not fracture filled?
The best way to ensure that you are not getting a fracture filled diamond is to insist on a grading report by a major gemological lab. Since these labs do not grade fracture filled diamonds, you can be sure that the diamond is not fracture filled if it is accompanied by a grading report by a major lab. For your proposal, I hope you are not considering a non-certified diamond.