Earlier this year a new gem treatment was introduced. Developed by Sithy Gems and Lapidary, in Sri Lanka, it is a new twist on enhanced gems. They call it “center-fused color treatment,” which at first sounds confusing. However, a little…

Introduction Since the supply of fine quality rubies and sapphires is limited, many techniques have been developed to enhance their appearance. In fact, no other gem species is subjected to as many types of treatment as corundum. Heat treatment…

Step 3: Practical Gemology Lesson 28 Back to syllabus While some gems are fairly easy to distinguish, others present greater challenges to gemologists. Two of the most difficult gemstone separations to make are scapolite from…

Step 3: Practical Gemology Lesson 26 Back to syllabus Disclosing enhancements is one of the most important responsibilities gemologists face. In fact, many countries are passing stricter laws about revealing gemstone…

Step 3: Practical Gemology Lesson 16 Back to syllabus Because surface treated gems are so common, it is important to know which treatments you are likely to encounter as well as how to test for them. Diffusion treatment, which…

Step 2: Advanced Gemology Lesson 11 Back to syllabus Assembled Stones It is common to glue two or three pieces of material together to make a single stone. Opals are frequently formed as doublets, a thin layer of opal on…

Step 2: Advanced Gemology Lesson 6 Back to syllabus Gemstone heat treatments can turn mediocre pieces into items of great beauty. Heating a gem to a specific temperature and then cooling it is a common procedure in the gem…

One of the most popular misconceptions about aquamarine is that its color should be just blue. Most consumers do prefer a dark blue aquamarine color. However, natural, untreated aquamarine is gemologically described as a transparent, blueish…

The answer is that not all Emeralds are treated, but the vast majority of them are. It’s like the heat treating of Sapphires… Assume they are treated until proven other wise. There are a lot of treatments being done on Emeralds. I do not in…

Two major problems plague the cut gemstone market: undisclosed gem treatments and substitutions of synthetic for natural gems. Gem buyers need to know these practices occur every day. They must learn how to protect themselves from fraud.