Emerald

The word "emerald" is derived from the Greek word "Smaragdos", which means "green stone". This is a fitting name, as emeralds are a rich green in color. Emeralds are the birthstone for those born in May. Emeralds also symbolize friendship, faithfulness and loyalty. These precious gems are also given out on a person's 20th, 35th, or 55th year of marriage. The emerald's color is also said to promote a calm and peaceful spirit.

 Emeralds, while always green, come in different SHADES of green. These shades are produced by the amount of chromium in the crystal. The more chromium there is, the more green an emerald is. Color is also determined by the different wave-lengths of light that the emerald intercepts while being formed. Hue, tone, and saturation also play a big part in the creation of the emerald. The hue gives the first impression of the color, the tone determines what color the emerald will be, and the saturation relates to the intensity of the emerald's final color.

All gemstones, including emeralds, are graded by their cut, color, size and weight. Emeralds are graded by this: Commercial, Good, Fine, and Extra Fine. All naturally made emeralds undergo special treatment within factories to improve their color and touch up the clearly visible imperfections, such as scratches on the emerald's surface a large cracks in the stone. The largest emerald ever discovered was the Mogul Emerald, which weighed in at a whopping 217.80 carats. Emeralds rank a 7 on the Mohs scale of hardness.