Comparison of Cold Laser and Hot Laser
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Laser inscription is the use of a very fine, precise laser beam to write a grading report number or customised personal message on the girdle (outside perimeter) of a diamond.
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Laser inscription will ensure that the loose diamond matches the Diamond Certificate.
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If the diamond is set in the ring it will also confirm that it is the same diamond as the one described on the Diamond Certificate.
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Our cold laser technology is the only laser technology that is 100% safe for diamonds.
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It is important to understand there are two very different categories of lasers used for diamond inscription - Hot Lasers and Cold Lasers.
Cold Laser :
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Cold laser inscription does not change the color or clarity grade of a diamond and is considered permanent.
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It can only be removed by a professional diamond cutter.
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NYGL uses the latest Cold Laser technology that allows excellent control during inscription without damaging the diamond (unlike a hot laser).
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Diamonds are transparent over a wide spectral range, down to approximately 220nm for type 2A diamonds.
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Cold lasers operate at
193nm and have a very short pulse duration.
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No pre or post treatment of the stone is necessary.
Hot Laser :
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Hot lasers are YAG lasers and Cold lasers use Excimer laser technology.
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Hot lasers will chip or fracture diamonds. High quality polished girdles are especially at risk for fracturing or chipping with "Hot" lasers.
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Hot lasers operate at a wave length above
220nm which means that the laser beam is able to penetrate through the surface of the diamond and into the stone itself.
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This produces a photo-ablative process, without the heat affect zone common to the thermal marking of other type of lasers.
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Additionally with a hot laser, pre and post treatment of the stone is necessary to help focus the laser beam on the surface of the stone.
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A clear white out material must be manually painted to the surface of the stone.
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Simply load the stone, verify your inscription on the live computer screen image of the gemstone and watch as the laser inscribes a perfect inscription or not!