Fake Emerald Comprises Slabs of Glass

RAPAPORT... Fraudsters created an imitation emerald by assembling fivepieces of glass around a beryl core using a "laborious multi-step cut-and-glueprocess," according to the Gemological Institute of America (GIA). The inside of the 3.35-carat stone - which the New Yorkbranch received for grading - was a natural beryl, a mineral ofwhich emerald is a variety. However, the crown consisted of a single piece ofglass glued onto the pavilion. The pavilion itself featured four interlocking, asymmetricalglass segments glued to the beryl core with colorless cement, the GIA explained. The act of creating the fake stone was probably lengthy andcomplex, GIA gemologists Tyler Smith and Augusto Castillo noted in the summer2018 issue of Gems & Gemology. At each stage of the creationprocess, the manufacturers attached one glass segment to the beryl core, and cutthe glass and the beryl to make a flat surface to which they could attach thenext piece of glass, according to the GIA's proposed model of how the assemblytook place. Once the artisans had stuck the four segments to the core,they polished it to create a flat surface onto which they added the glass crown. The GIA researchers initially spotted multiple, nonparallelcement planes when examining the stone under a microscope. Further tests confirmedthe presence of glass. Fraudsters have imitated precious stones using assemblagesof various materials for centuries, with records of such activities dating backto Roman author Pliny the Elder's Natural History in the first century, the GIAexplained. However, this was the first time the New York or Carlsbad laboratorieshad received an assembled stone of this type. "Since all exposed surfaces were glass, it is assumed thatthe stone was fabricated relatively recently due to the sharp facet junctionsand lack of wear," the authors said. "It is intriguing that an antiquatedtechnique is updated in modern times, serving as a cautionary tale of theingenuity counterfeiters employ." Image: Tyler Smith/GIA