Emeralds

May’s birthstone, the emerald, belongs to the beryl mineral group and receives its green color from chromium and sometimes vanadium. But only the greenest hue may be called an emerald. Pale green is merely known as “green beryl.” To be considered a top gem, an emerald must be highly transparent and contain a pure, lush green hue. Most emeralds have many inclusions, so they can be very brittle and easily broken. Clearly, Oz should have chosen better building materials.

Emeralds are graded by the naked eye, rather than with a loupe, as diamonds are graded, so if an emerald has no inclusions visible to the naked eye, it is considered flawless. But surface-breaking fissures are common in emeralds, so most are oiled to enhance their clarity. The levels of enhancement are also graded in four steps: none, minor, moderate, and highly enhanced. Two stones that may seem to be of similar quality may actually have vastly different treatment levels. So if you are looking at a high quality emerald with a “moderate” enhancement level, you should expect to pay 40-50% less for that stone than you would for an identical stone with a grade of “none.” Colombian emeralds are most treasured for their transparency and fire.

A very rare type of emerald known as “trapiche” is sometimes found in Columbian mines. This type of emerald contains dark carbon impurities that give it a star-like pattern. This is not the same as asterism, because the pattern is not caused by light reflection from tiny inclusions. The name “trapiche” comes from a wheel used to grind sugarcane in the area.

Buying Your Emerald

As mentioned, only the purest, grass-green beryl is an emerald. If you have your heart set on a flawless emerald, you will either pay a very high price for it, or you will need to look for a lab-grown emerald. Synthetic emeralds can be made in many ways, but only the laboratory-grown emerald is made by humans through the same process used by Mother Nature. That means it is almost indistinguishable from a natural emerald.

If you purchase a genuine emerald that has been treated (and remember that most of them have), you should never wash it with soap or use an ultrasonic jewelry cleaner on it. Doing so will remove the oil and expose the internal flaws the oil was used to hide. You must also be careful not to bang the jewelry or expose it to temperature extremes, as this may cause internal cracks to form. When you purchase a genuine emerald, it is important to get a certificate, especially if it is expensive. And if you make your purchase over the Internet, be sure to deal with a reputable jeweler.

Emeralds are very popular among those of Irish ancestry and they look stunning in jewelry with a Celtic design. Whatever type of jewelry you’re considering, Jeweler.com can help you find the emerald that’s just right for you.