Gemex and Megascope
- Thread starter mybks73
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- Sep 3, 2000
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Gemex is a way of giving light return information to consumers and is used by a small number of retailers and retail chains. It is not scientific enough for those of us that have found better equipment, but suits some retailer's sales goals and also fits consumers who prefer their information in a simplistic manner that is visually effective, but not able to clearly discriminate categories at the very top end of light performance from one another as well as some newer methods. The top Gemex grade may be considered overly broad in much the same way the GIA ExExEx grade is often described as a bit overly broad. A Gemex report does not rule out a diamond, but it is not the way to select a diamond, either. It is a part of screening potential choices.
A Megascope is a measuring device, much like a Sarin or Helium, but is not a gemstone grading device. While none are identical, they all do approximately the same thing, measure the physical dimensions. Any Ray Tracing program found in the Megascope software, or Sarin software is not the current way of assessing light behavior, either. DIamCalc software is very useful in such light return assessments because it has been more extensively developed and verified.
When you see a Gemex report, also find out the name of the Laboratory where the grading report was created. Likely it will be other than GIA or AGSL. Not every other lab using GIA grading nomenclature is using the same grading standards, so it can be misleading. In recent times I have found GSI lab reports pretty reliable and way better than some other competing labs. GCAL is highly reliable, PGI is also highly reliable, but less well known. GS Lab is not the same as GSI Lab, so don't be confused. Almost any lab report gives you good physical measurements and reasonable accuracy on fluorescence, but unfortunately there are many labs which fail to give understandable and uniform color and clarity grading based on the GIA system of grading even while they use, or abuse, the same terminology that GIA uses for their reported grades.
A Megascope is a measuring device, much like a Sarin or Helium, but is not a gemstone grading device. While none are identical, they all do approximately the same thing, measure the physical dimensions. Any Ray Tracing program found in the Megascope software, or Sarin software is not the current way of assessing light behavior, either. DIamCalc software is very useful in such light return assessments because it has been more extensively developed and verified.
When you see a Gemex report, also find out the name of the Laboratory where the grading report was created. Likely it will be other than GIA or AGSL. Not every other lab using GIA grading nomenclature is using the same grading standards, so it can be misleading. In recent times I have found GSI lab reports pretty reliable and way better than some other competing labs. GCAL is highly reliable, PGI is also highly reliable, but less well known. GS Lab is not the same as GSI Lab, so don't be confused. Almost any lab report gives you good physical measurements and reasonable accuracy on fluorescence, but unfortunately there are many labs which fail to give understandable and uniform color and clarity grading based on the GIA system of grading even while they use, or abuse, the same terminology that GIA uses for their reported grades.
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