Gemstone Quality Assurance

Learn about tools and techniques that will help you with gemstone testing.

Video Transcript

When working with gemstones, quality assurance is always a top priority.  Extensive testing must be done to ensure the quality of the gemstones that you buy and sell.  Here we will share with you some of the techniques and tools that will help you sell with confidence.

The key instruments used to test gemstones are a refractometer, polariscope, binocular microscope, and a ten power loupe.  Make sure the stone you are inspecting is clean and polished.  With a 10 power loupe, observe the stone for color, transparency, cutting style, and any unusual phenomenon.  Next use the refractometer to obtain a reading on their refractive index.  Be careful not to use too much liquid.  The polariscope is then used to find out if the gem is singly or doubly refractive.  This is the optic character of the gem and will help identify the material of a stone. As you move the stone around you are looking for any changes in light or any blinking.  These findings along with the refractive index are then compared against a gem property chart to find a match.  This will tell if the stone is spinel, corundum barrel, etc., however testing is not complete.  Using the binocular microscope look deeper into the stone and look for any unusual characteristics that give signs of enhancements, fillings, etc.  These unique inclusions act like fingerprints and help easily identify certain gem types.  After these tests are completed you can be almost one hundred percent certain of the gemstone and its quality.
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9/18/2020 Market Prices:
Gold 1950.85 Platinum 937.00 Silver 27.06