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What is a Gemmological Laboratory Test?

Gemmology is the study of the ‘Science of Gemstones’. So very simply what that means is, that a trained Gemmologist is able to diagnose the Identification of a Gemstone by scientific testing.

A full Laboratory Sheet is used and a battery of scientific tests are carried out.

· 10X Loupe – for external & internal visual inspection

· Refractometer – to ascertain the Refractive Index, Optic Character & Birefringence of the stone

· Dichroscope– to ascertain the Pleochrism or Trichroism of the stone

· Polariscope – to ascertain whether the stone is Singly or Doubly Refracting, also to orientate the Optic Axis

· Spectroscope (Prism or Diffraction) – to ascertain the absorption pattern made by each stone by the chemicals present

· Microscope – for high magnification inspection, which helps to differentiate natural or synthetic gemstones, as well as many other tasks

· Specific Gravity Scales – to ascertain the actual Specific Gravity of the gemstone

· Ultra Violet Light Source – Long Wave/Short Wave UV will produce different effects with different stones

· Colour Filters – to help ascertain the colour reactions within the stone which gives us clues to the chemicals within the stone

Once we have all the relevant information we can then combine all the facts and come

up with a Conclusion.

Stones can be tested while still set in the item of jewellery, but it is much easier if the stone is loose. In saying that, I would say 80% easily of my Lab Testing would be for set stones.

It takes 2 years of intense study to become an Accredited Gemmologist, and continuous study & updates to keep abreast of the market information, which is forever changing, especially when it comes to treatments of stones. Don’t get me started!

Just a little collage of some of the Gemmological Certificates Matthew & I have earned over the years… and this does not include our Valuing Credentials and International Level Diamond Studies! Never enough wall!!

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