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Treatments and Enhancements

Enhancement is defined by the American Gem Trade Association’s (AGTA) “Gemstone Information Manual”, as “…any traditional process other than cutting and polishing that improves the appearance (color/clarity/phenomena), durability or availability of a gemstone.”

A gemstone enhancement is considered permanent as long as the effect of the enhancement does not change under normal wear, cutting, repair, cleaning, or display conditions. If a gemstone enhancement is not permanent, appropriate disclosure is required.”

All gemstones sold or consigned from Boston Gems will have a disclosure code on all invoices and/or memorandum forms indicating whether the gemstone has been enhanced and what type of enhancement has been applied.

All natural gemstones can be divided into three basic categories:

Those which are not enhanced

There are some gemstones which are not currently known to be enhanced such as alexandrite and garnet. However, there are particular gemstones that normally receive enhancements that do not need treatment due to their natural beauty. In these cases Boston Gems will provide a guarantee that there has been no enhancement done to the gemstone.

Those which are normally enhanced

There are many acceptable gemstone enhancements that are difficult to detect. In these cases, aquamarine, quartz, topaz, emerald, Boston Gems will assume the enhancement has been applied and disclose accordingly. This assumption is made to protect Boston Gems as well as the buyer. We will always use the specific enhancement code to describe an acceptable treatment.

Specific enhancement for specific gemstones

There may be gemstones that are treated by unconventional techniques that utilize poor material and change the appearance and price significantly. Lead glass filled ruby would be an example of this type of enhancement. Surface diffusion and assembled stones are also examples of specific enhancements for specific gemstones. In this case Boston Gems will not only disclose the treatment, but will specify any special care needed for the gemstone. Boston Gems does not promote the sale of such gemstones.
List of codes Defined below are the specific enhancement codes and designations used by AGTA and Boston Gems

AGTA Gemstone Information Manual>

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N Not currently Enhanced:

B Bleaching:

C Coating:

D Dyeing:

F Filling:

H Heating:

HP Heating and Pressure:

SYN Synthetic:

IMIT Imitation:

ASBL: Assembled

I Impregnation:

L Lasering:

O Oiling/Resin Infusion:

R Irradiation:

U Diffusion:

W Waxing/Oiling: