An Introduction to Gem Treatments and Care

Most gemstones on the market today have been modified by mankind in one way or another. Some gemstones such as Peridot, Csarite® and Garnet are not enhanced at all (other than the cutting and polishing) but there are many gems such as Tanzanite, Emerald, Sapphire, Ruby and Topaz that are normally enhanced.

As a lot of treatments are carried out whilst the gem is in the raw crystal stage, it’s even often impossible to be 100% sure what enhancements have been made to a particular gem. We can, however, provide information about the most common treatments that certain gemstones undergo.

Many of these enhancements have been practised for thousands of years. The dyeing of Agate is one example. Others, such as irradiated Blue Topaz, are solely a product of the technological advances of the modern age. Enhancements often have an impact on the value of precious stones, with the highest prices paid for natural gems of fine quality that have not been enhanced in any way beyond ordinary cutting and polishing.

Four ‘rules of thumb' for Gem Collectors

  1. Gem Collector only sells genuine gemstones, many of which have been enhanced.
  2. For most gems today, enhancements are a basic part of the finishing process.
  3. The market place sets the values of both natural and enhanced gems.
  4. Since certain enhancements are undetectable or difficult to detect, the Gem Collector approach is to assume that all items are enhanced unless there is specific gemmological evidence that shows the item has not been enhanced or the item is of a type for which enhancements are not typically used.

For more information please download our "Introduction to treatments and care" PDF.
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