The Characteristics and Identification of Filled Diamonds

Abstract

helped with the chemical analyses. The assistance of Eli Haas and Martin Rapaport was invaluable. Unless otherwise noted, all pholomicrographs are by John I. Koivula. This study was supported in part by the Dr. Byron C. Butler Fund for tnclusion Research.

Identification and Durability of Lead Glass-Filled Rubies

“…Where filled cavities were large enough, spherical gas bubbles were sometimes visible. This was reminiscent of the features we first noted in clarity-enhanced diamonds 18 years ago (Koivula et al, 1989). Although the filling material in rubies might be different, the effect of the treatment-to minimize the visibility of fractures and cavities-was almost identical to that achieved with fracture filling in diamonds.…”

“…This test was shown to be successful in detecting the high-lead-content glass used for filling fractures in diamonds many years ago (Koivula et al, 1989), working on the basis that lead glass strongly absorbs X-rays. As expected, the lead glass-filled fractures in our samples were easily visible in the Xradiograph (figure 19).…”

New Filling Material for Diamonds from Oved Diamond Company: A Preliminary Study

“…As was reported for Yehuda filled diamonds as early as 1989, the most characteristic visual feature of diamonds filled with such a glass is the flash effect (see, e.g., Koivula et al, 1989; and the report on Yehuda, Koss, and Goldman Oved treated diamonds in Kammerling et al, 1994). This was also the case with the new Oved diamonds.…”

“…Within a short time, this treatment became widespread. Concerns about the identification of these treated diamonds, and about their durability during jewelry manufacturing or repair situations, led to a series of articles that described this material (Koivula et al, 1989;Scarratt, 1992;Nelson, 1993Nelson, , 1994Kammerling et al, 1994;Nassau, 1994;McClure and Kammerling, 1995).…”

Identification of Bleached and Polymer-Impregnated Jadeite

“…The most prominent are diamond (Koivula et al, 1989), emerald (Kammerling et al, 1991), and now jade. The purpose of such treatments is to match the index of refraction of the impregnation material to that of the gem to be enhanced, thereby minimizing the visibility of fractures.…”