May’s birthstone is the lovely, verdant emerald and we’re green with envy for every May baby who gets to rock this beautiful birthstone. Emeralds have been treasured for millennia, dating back to 300 BC when the first emerald were discovered in Egypt. Today, the vast majority of emeralds come from Colombia (we are not aggressive buyers of loose Colombian emeralds, we prefer to purchase antique emerald estate jewelry as-is.)
Emeralds are the most well known members of the beryl family, which means that they have a hexagonal crystal structure. They receive their famous green color from small amounts of the minerals chromium and vanadium.
Like diamonds, emeralds are graded by their 4 C’s:
- Carat Weight
For the most part, the same rules apply to emeralds as do to diamonds – the bigger the better(carat), the more precise the proportions, all the more perfect(cut) – but there are two big exceptions.
The stones cover a huge color spectrum – as long as they’re green. From light yellow-green to dark, rich blue-green, emeralds come in a ton of different shades. However, only stones on the darker end of the spectrum are considered true emeralds. Lighter green stones are classified as green beryls. As a general rule (and opposite from diamonds) the more intense an emerald’s color, the greater its value.
When it comes to clarity, emeralds tend to contain many inclusions and fissures. This is because of their crystal structure. Like diamonds, the highest quality (and most expensive emeralds) have the least inclusions. However, unlike diamonds, emeralds are graded for clarity by the naked eye. If no inclusions are seen the gem earns a “flawless” grade.
Emeralds are a relatively tough 7.5 on the Mohs scale of hardness, but those inclusions and internal characteristics make them more prone to breakage. It’s for this reason we caution against emeralds as everyday wear (for example in an engagement ring) unless they’re set in a very protective engagement ring setting.
The rarity and expense of natural emeralds made them a prime candidate for synthetic production. Synthetic emeralds, which are lab-grown crystals identical in structure to natural stones, have been available since the early 1960s and continue to grow in popularity. The emerald market is also ripe for treated stones – mostly clarity treatments and occasionally some high pressure treatments to enhance color. We prefer to buy natural, untreated emeralds, but if the piece is interesting enough we’ll make an offer. Then, as is our policy, we disclose, disclose and disclose again any treatments to our interested clientele.
We love emeralds, this birthstone is rich, beautiful, and one of our favorite gemstones. It’s always hard to pick a favorite from the precious gem trio of ruby, emerald and sapphire, but you’ll notice a ton of antique emerald jewelry in our estate cases at Raymond Lee Jewelers – we can’t get enough!