Laboratory Director of AGTA
Gemological Testing Center

Monday, October 3rd, 2005

Dr. Lore Kiefert, the Laboratory Director of AGTA-GTC, presented an extremely information-packed lecture. She introduced us to the inside workings of the AGTA Gem Testing Laboratory, the advanced instrumentation used, and the interesting results that often surprise even the best of experts.

Speaker Lore Kiefert

Her PowerPoint presentation included a detailed array of photographs of many gemstones and their natural and enhanced characteristics. Dr. Kiefert shared the step-by-step processes needed to identify, find the origin of, and recognize treatments of the 400 to 500 gemstones handled by the laboratory each month. Currently some of the issues of most concern are the HPHT treatment of diamonds, the fissure filling of emeralds, and ruby and sapphire diffusion. The AGTA laboratory also provides quartz batch testing at very low costs as well as pearl identification.

Setting the stage for a raffle win

New gemstones appearing on the market from new sources like Madagascar can create confusion as to origin identification. Lesser known treatments of synthetic materials with organic substances and heat also creates new challenges. Type identification of diamonds, which is essential in identifying HPHT-treated diamonds, was explained in detail. It was rather disturbing to hear that thousands of the fairly new beryllium-deep-diffusion treatment sapphires had been “certified” by an Asian laboratory as “natural” and were sold as such for several years. The current widespread use of this treatment explains why so many more orange colored sapphires are finding their way into the market-place, with proper disclosure still being rather inconsistent.

Lore shows examples to Chih-Shue Yan and Randy Petersen

Determining color authenticity of pearls is also a regular part of the laboratory’s tasks, with Gulf-of-California pearls making a reentrance, having been an old source of naturally black and silver-colored pearls, often with a brownish to greenish overtone, and red fluorescence. Along with rare and valuable items, many imitation pearls are also submitted for inspection. With the popularity of items of organic origin, Dr. Kiefert shared some pointers as to the identification of dyed and resin-filled red and blue coral.

Bobby Mann and Dennis Nelson chatting

A huge amount of useful gemological information was covered, which triggered a good amount of discussion. Dr. Kiefert�s active involvement in the industry allowed her to speak about the new demantoid garnets from Iran, New Zealand sapphires, and a new mineral which was mistakenly first called “raspberry beryl,” but ended up being neither a raspberry, nor beryl. One very intriguing story about a rough emerald crystal, which still holds a secret in the form of a paper with Arabic writing, captured the interest of all who attended.

Chapter president Toby Fitzkee with Deborah Dern

Dr. Kiefert is an impressive lecturer, reflecting her vast knowledge of the subject and her prolific writing background. She has a Masters degree in Mineralogy and earned her Ph.D. in 1996 and her FGA in 1998. Her courier has taken her from The Swiss Gemmological Institute to the AGTA Gemmological Testing Center in New York City, where she currently resides.

Written by Denise Nelson

Photographs by Bill Scherlag