Dr. Raul Berenguel, PhD.
Dr. Raul Berenguel holds degrees in History (Scientific Branch, 2008) and Contemporary Art (PhD, 2012) from the Universidade Aberta. He has specific expertise in the fields of history, gemology, and contemporary art. In addition, he’s also an expert in applying traditional gemological techniques to investigating art objects made from gem materials.
Articles by Dr. Raul Berenguel, PhD.
How to Build Pocket Crossed Filters for Gemstone Testing
The crossed filters technique allows gemologists to detect chromium in gems. Learn how to build a portable device for conducting...
How to Measure an OTL Gemstone Refractive Index
Measuring “over the limit” (OTL) refractive indices can help distinguish diamonds from simulants. You can do this with a simple...
How to Evaluate Diamond Symmetry
How can you evaluate diamond symmetry without an expensive proportion scope? Learn how to build an inexpensive alternative tool that...
Specific Gravity Testing Part 4: Refining Your Specific Gravity Testing Techniques
Factors like liquid temperature and inclusions can affect a gem's density reading. These specific gravity testing techniques can improve your...
Gemstones and Refraction Liquids
Gemologists use refraction liquids to identify gemstone refractive indices (RI). Learn about the properties of these liquids and safe RI...
How to Build a Multipurpose Microscope Stage for Gems
A multipurpose microscope stage can help you move, view, and photograph gemstones under magnification easily from many angles. Learn how...
Build Your Own Gemology Tools
Are you a hobbyist or professional gemologist facing high equipment costs? Read our IGS series of articles that can help...