AGL Modifies Wording on Heated Rubies

The American Gemological Laboratories (AGL) recently announced that it will change the terminology used for heat-treated rubies from “inorganic [flux-type]” to “heating residues.” The decision came after much discussion on the issue with AGL clients, gem traders and industry members to make AGL’s nomenclature on heated rubies consistent with other gem labs. 

The use of fluxing agents during the heating process of rubies results in a combination of features or materials being deposited and remaining along the newly healed fissures, according to Christopher Smith, AGL’s president.

AGL president Christopher Smith.

The previously open fissures are replaced by planes consisting of re-grown ruby (synthetic), solidified vitreous melt (glass) and voids (empty bubbles). The relative amount of these three parts depends on many factors. To better try and communicate the multiple and complex nature of these remaining bi-products, many labs around the world starting using the term “heating residues” with terms describing the relative quantity (such as: minor residues in fissures), the gem lab announced in a recent press release.

The AGL also announced that it will continue to offer their FastTrack services of GemBriefs, our lower cost alternative in a convenient credit card-sized format.

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