Let’s start with this: Emerald is a beryl, like Auqamarine. While emeralds are relatively high on the Mohs scale (7.5-8), they almost always have inclusions, which makes them suceptible to breakage.
While diamonds are examined under a loupe to determine if they are flawed, an emerald is examined with the naked eye. If no inclusions can be seen, the emerald is considered to be flawless. Most emeralds will have inclusions, as mentioned above, and most will have fissures that reach the surface of the stone. Almost all emeralds are oiled (coated with a durable oil coating) to enhance the appearance of clarity.
The best emeralds are medium to dark in hue, and distictly green. While emerald can be yellow-green to blue-green, or even offer a hint of red, to be an emerald, it must be green. In the United States, ‘vanadium emeralds’ (beryls whose green colour is derived from vanadium, rather than chromium) have been considered true emeralds since the 1960s. In other parts of the world, the definition of an emerald does not include these ‘vanadium emeralds’. A special filter was developed to distinguish between ‘vanadium emerald’ and traditional emeralds.
Emerald is regarded as the traditional birthstone for May, as well as the traditional gemstone for the astrological signs of Taurus, Cancer and sometimes Gemini. It is also considered by some to be the traditional gift for 20th, 35th, and 55th anniversaries. (The ring in the picture, above, was designed by my father for my mother, on the occasion of their 35th anniversary.)
Emeralds have been said to bring good luck and good health. In ancient Rome, it was sacred to Venus, godess of love and fertility. While much of the lore of emerealds’ power revolves around themes of spring – life, growth, fertility, hope – the emerald has also been said to bring the wearer wisdom. It has also been said to have the power to heal, particularly the heart (physical) and eye, and to be a bridge between two people, creating stronger ties of love.
Never place an emerald in an ultrasonic cleaner or steam cleaner, as these can damage the stone. Emeralds should be cleaned with a soft brush and mild soap, not too frequently (remeber, they fracture easily and are oiled to improve their appearance!). Professional cleaning is always an option, and many jewellery stores will be able to re-oil an emerald for you should it require it.