Emerald Transformation: Cleaning and Recutting a Natural Emerald
To meet the demand for fine emeralds with no clarity enhancements, dealers search for gems to clean and recut. Learn how this emerald transformation works.
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Emerald Transformation, Step 1: Cleaning
This Shakiso, Ethiopian emerald with a minor clarity enhancement had only one major issue: a reflective fracture on its corner. This only came to light after a thorough cleaning. Fortunately, Colombian emerald cleaning and treating experts Consuelo "Connie" Infante Galindo and her husband, gemologist Darwin D Fortaleché (formerly of CDTEC Bogotá, now Guild Gemlab Bangkok), accomplished this tricky task. Thorough cleanings often require weeks of soaking in various solvents.
Emerald Transformation, Step 2: Recutting
Bangkok is also blessed to be the new home of one of the world's finest emerald cutters, Mª ︎"Mafe︎" Fernanda Argotty, a second-generation lapidary artisan also from Bogotá, Colombia. Not surprisingly, I chose Mafe to take on this difficult and important project. After several days carefully studying the emerald, she plotted out the stone and formulated a course of action with the goal of finishing over the pivotal, price-critical 10-ct marker.
Completely eliminating the reflective fissure meant removing one corner of the stone. Therefore, the entire emerald had to be recut in order to maintain a pleasant and well-balanced final shape. With skill and expertise, as well as specialized equipment imported from Israel, Mafe finished the stone at 10.17 cts. This was a loss of only 1.05 cts, or slightly less than 10%, so we celebrated with some freshly brewed Japanese green tea!
Getting the Lab Report
Next came the challenge of obtaining a report with no indication of clarity enhancement from a respected lab. Not surprisingly, the first submission came back with an indication of insignificant residue in a surface-reaching fracture left over from the cutting process. This was unacceptable, so the stone went back to Connie and Darwin for re-cleaning.
After another week of waiting patiently, Darwin issued a Guild Gemlab report stating the emerald was "laboratory clean." However, for buyers of exceptional no-oil emeralds, just one lab report never suffices. So, we were also relieved to receive two more "no clarity enhancement" reports, from Bellerophon Gemlab, signed by Martial Curti and emerald expert Dr. Dietmar Schwarz, as well as from ICA GemLab, signed by Kenneth Scarratt.
Jeffery Bergman, SSEF SGC
With humble roots from a non-gem trade family, as a lapidary hobbyist, Jeffery cut and polished his first gemstone at the age of fourteen launching him on a lifelong career which has taken him to more than 70 countries, and every continent except Antarctica. With 5 decades of broad-based experience in natural gemstones, diamonds and fine jewelry, in 2020 Jeffery founded Eighth Dimension Gems (formerly Primagem) in Bangkok, Thailand, where he has lived for over 30 years.
Jeffery’s formal gemmological training was accomplished at the prestigious Swiss Gemmological Institute in Basel, Switzerland where he passed requisite exams for his SSEF Basic Gemmology (BGC) and SSEF Basic Diamonds (BDC) Diplomas. Additionally, he completed SSEF’s Advanced Pearls (ATC), Advanced Colored Stones (ATC), and Scientific Gemmology (SGC) courses.
Featured in many gem and jewelry periodicals, Jeffery has also appeared in interviews on the ABC, BBC, CCTV, CNA, CNN, NBC and GEO. He has been quoted in Time, USA Today, National Geographic, Discover, GIA’s Gems & Gemology, Gem-A’s Journal of Gemmology, ICA’s InColor, Rivista Italiana di Gemmologia/Italian Gemological Review and many other publications around the world. A guest speaker at seven GIA Gem Gatherings as well as many gemological conferences & universities, Jeffery is also an Honorary Professor for the AIGS – Asian Institute of Gemological Sciences in Bangkok, Thailand.
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