sardonyx - birthstone gemologysardonyx - birthstone gemology

Take the Birthstone Quiz

What do you know about birthstones? Take our short birthstone quiz and learn about the makeup, cutting, and value of these popular gemstones.

You might be familiar with the romance of birthstones, but how much do you know about these gemstones? Take our short birthstone quiz and learn about their composition, cutting, and value.
sardonyx - birthstone quiz
The traditional or ancient birthstone for August, sardonyx is red and white layered onyx, a variety of chalcedony, itself a variety of quartz. Gem with intaglio of Bellerophon and Pegasus, sardonyx and gold, early 1st century CE, Roman Empire, from the collection of the Walters Art Museum. Photo licensed under CC By-SA 3.0.

What is My Birthstone?

Throughout history, people have given poetic meanings to different gemstones. Nowadays, our use of birthstones is probably the best-known example of this practice. Each month has a special stone assigned to it. For those born in a particular month, that month's gem purportedly acts as a "good luck" charm. Of course, birthstones and their meanings vary across cultures. Below you'll find a list of birthstones commonly used in English speaking countries.




NovemberGolden Topaz or CitrineTopaz
DecemberBlue Zircon or TanzaniteTurquoise or Lapis

The "modern" list was created in the early 20th century. However, it never really replaced the "ancient" or traditional list. It became more of a supplement. Today, people freely choose between modern and ancient options. In addition to these, some people consult alternative birthstone lists, including lists based on astrological signs and birth hour.

In Germany and Scandinavian countries, gem enthusiasts prefer moonstones like these as the June birthstone. Photo by Gaia Metal Studio. Licensed under CC By-ND 2.0.

Birthstone Quiz

Which Birthstones are Minerals?

Which Birthstones are Usually Cut as Cabochons?

Which Birthstones are the Most Valuable?

emerald - birthstone gemology
Emerald bracelet. Jewelry and photo by Mauro Cateb. Licensed under CC By 2.0.

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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