Hybrid Gemstones: Glass Rubies and More
Some gems contain both natural and lab-made components. Learn about these hybrid gemstones and how to distinguish them from mined gems.
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 upgrade to…
May Birthstone: Emerald
What is the Birthstone for May? The birthstone representing May is emerald, a rich green variety of the diverse beryl gem group which must exhibit…
Why We Love Montana Sapphires and Yogo Sapphires
With rich cornflower blue Yogo sapphires and fancy-colored gems in any color of the rainbow, Montana sapphires are a great choice for any jewelry…
32 Green Gemstones (How Many Do You Know?)
A favorite color for nature-inspired designs, green gemstones never go out of style. Learn which of these 32 green gems hold up best for engagement…
April Birthstone: Diamond
What is April’s Birthstone? The birthstone representing April is diamond. The vast majority of diamonds are transparent, colorless, and show…
Sphalerite Buying Guide
Our sphalerite buying guide can help you learn how these gems are graded, what to avoid, and how to identify a high quality stone or a bargain in the…
Gem Origin Opinions: When Gemology Labs Agree to Disagree on Sapphire Origins
Why do gemology labs sometimes have different gem origin opinions, especially for sapphires? Learn the science and history behind the debate.…
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