The Art and Science of Identifying Gemstones
The Art and Science of Identifying Gemstones

Professional Gemologist Certification Course

The Art and Science of Identifying Gemstones

One of the biggest mistakes beginning gemologists make when identifying gemstones is over-relying on data. After conducting some initial tests, they consult long lists of potential species. It’s easy to get lost in a sea of data and overlook important clues. Gemology is as much art as science, and relying strictly on analytical skills can hamper your work. Learning gemology requires not just practicing testing techniques but also improving your deductive reasoning.

Below you’ll find an outline that combines traditional gem testing techniques with the possibilities modern gemology software offers. This step-by-step procedure also emphasizes developing your deductive reasoning as an essential skill for identifying gemstones.

Gemology Tools Software

The Gemology Tools software makes the gemstone identification process more efficient. Enter your test results in the database program and let your computer cross-reference the data and search for possible matches.

The data searching features of Gemology Tools are so powerful you can do things never before possible. I have developed new procedures to take advantage of this inexpensive software that simplify the identification process and reduce the lab work and time required.

In a traditional gemological approach, the refractive index (RI)...


Donald Clark, CSM IMG

The late Donald Clark, CSM founded the International Gem Society in 1998. Donald started in the gem and jewelry industry in 1976. He received his formal gemology training from the Gemological Institute of America (GIA) and the American Society of Gemcutters (ASG). The letters “CSM” after his name stood for Certified Supreme Master Gemcutter, a designation of Wykoff’s ASG which has often been referred to as the doctorate of gem cutting. The American Society of Gemcutters only had 54 people reach this level. Along with dozens of articles for leading trade magazines, Donald authored the book “Modern Faceting, the Easy Way.”


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