An emerald, how beautiful!

May’s traditional birthstone is emerald. It seems like a wonderful option for the northern hemisphere, rich green just as the buds are unfurling into proper leaves.

Emerald is a type of beryl. (From aluminum beryllium silicate.) The word itself comes from the Greek for green stone, and probably did originally refer to most green stones. The stone has been known since ancient times, the Greeks and Romans used them and made fakes out of glass, as did the Egyptians. Cleopatra was said to have emerald mines among her vast wealth. (And there is some evidence that that is truth rather than rumor.) Probably the most beautiful emeralds I’ve ever seen were in ancient jewelry in the British Museum. I later years the Spanish plundered large quantities of emeralds from the New World as well as their hauls of gold and silver.

The trace elements chrome and vanadium both make beryls green, but traditionally only beryls colored green through traces of chrome are considered emeralds. Gemologists are still debating if a vanadium green beryl is a true emerald. (The authors of my assorted books all disagree with each other as well. It sounds like there isn’t an official decision if gems are to be classified by color or by chemistry.) Emeralds are one of the few precious stones where inclusions are expected, a too clear gem is considered suspect. Inclusions are euphemistically called jardin– french for garden- reflecting the shape combined with the color of the stone. (Probably my favorite euphemism for flaws…) Some translucency is a plus, and the deeper greens with a hint of blue are the most valuable.

The classic emerald cut was designed to reduce the fragile spots on the stone, since they are sensitive to knocks.

A movie moment in honor of emeralds and their fascinating color. Gigi learns about jewelry from her aunt, and to look for that hint of blue that makes an emerald so stunning. (And also a nod to Mother’s Day. The ‘topaz, among my jewels, are you mad’ line is a running joke with my mother…)

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3 Comments

Filed under Gems

3 responses to “An emerald, how beautiful!

  1. Pingback: A Note on Inclusions | Magpie's Miscellany

  2. It’s good enough for elves, too! What about the other beryls? Are they always green?

    • Nope, just the most famous. The colors come from different trace elements.
      (Which is why I’m wondering if chrome diopside is a similar green because of the chromium, I’m not sure how to get a low level explanation of how elements influence mineral colors!)
      There’s the whole debate over if it’s vanadium green if it’s still an emerald, and certain iron ions make Aquamarine. There’s also pinks and yellows.

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