In the first several decades of the modern study of gems, most of the threats to the integrity of natural stones could be handled with basic gemological equipment and techniques. Criteria were developed from the investigation of known samples, and clear (and often simple) means were used to properly identify the gems in question. However, the decade of the ‘80s ushered in technology that would change the face of gemology as we knew it. It started innocently enough with the use of higher temperatures in a controlled environment to heat corundum, a direct result of the availability of more sophisticated furnaces. While heat treatment certainly was not new to the gemological community, the impact that these advanced processes could have on the salability of otherwise worthless material was significant. The best example might be the milky-white “geuda” rough that could be dramatically transformed into beautiful blue sapphire.

The lead article in this issue is virtually an issue in itself. The authors, a team led by noted scientist Dr. John Emmett, have examined the most serious threat to corundum (and the colored stone market) in the past quarter century and reached some important conclusions in a remarkably short period of time. They not only explain the so-called lattice diffusion of beryllium (Be) into corundum, but they also describe unanticipated consequences of the procedure as well as criteria for proving or indicating that it has been used. Whether accidental or deliberate at its outset, Be diffusion has set new boundaries for heat treatment and has caused those who study the subject to question whether, in this case, the treaters have simply gone too far. The process not only involves heating the ruby or sapphire at high temperatures, so a foreign color-changing element (Be) can be introduced, but it also may cause recrystallization of areas of the treated stone, which are distinctly synthetic.

Gemological laboratories around the world have their work cut out for them. The authors point out that if the diffusion penetrates only the near-surface area of a polished stone, as with the first “padparadscha”-like Be-diffused sapphires, standard gemological testing should identify the material. However, since the time that this treatment was first discovered in late 2001, we have learned that it can be refined so that it not only penetrates the entire sapphire to impart attractive yellow-to-orange hues, but it also produces attractive rubies from purplish or brownish red stones, as well as lightens dark blue sapphires. And in many cases, proof of treatment can be obtained only with advanced analytical techniques.

While there is nothing inherently wrong with treatments of any kind—provided they are properly disclosed—this treatment is more insidious. Sophisticated SIMS or LA-ICP-MS analyses are simply too costly for all but the most valuable specimens. The inevitable result is that some buyers will only consider sapphires and rubies with no evidence of treatment, and discount those with any evidence of treatment. This has already hurt those who carry goods that have been simply heat treated, with no foreign elements added. The corundum industry now finds itself battered by the very treatment that some thought would lead to growth and profits.

What is the lesson to be learned here? Let us remember the caveat “disclose or be disclosed” that ethicist Rushworth Kidder gravely issued to attendees at GIA’s International Gemological Symposium in 1999. It is inevitable that, over time, any doctoring of gem materials will be found out and will, if not properly disclosed, have detrimental results for both the proponents of the treatment and the gem trade as a whole. The harm that can be caused as a result of either passive nondisclosure or willful intent to deceive is irreparable.

Just as the debate on human cloning rages in the medical field, so will the debate over lattice diffusion in corundum continue in ours. There is no right or wrong answer for gemology. It is not a moral issue to treat or not to treat. But it is a moral issue to disclose or not to disclose. At GIA, we urge full disclosure and openness to dialogue as soon as a new treatment is developed, and long before it is introduced to the market. This is the only enlightened approach to avoiding problems like the one we currently face. Doing the right thing for the industry and the public will, inevitably, be the right thing for the commercial success of new treatments.

William E. Boyajian, President
Gemological Institute of America