“Imitations” are materials that have a similar appearance to natural gems and are used in their place. They are often manufactured specifically to serve as substitutes. Green glass, synthetic green spinel, green cubic zirconia, and green yttrium aluminum garnet are common imitations used in place of emerald.

The first synthetic emeralds were produced in the mid-1800s, but it was not until the 1930s that Carroll Chatham began producing synthetic emerald in commercial quantities. Once commercial production began, a steady supply of synthetic emeralds began entering the market. To date, several companies including Chatham Created Gems, Gilson, Kyocera Corporation, Lennix, Seiko Corporation, Biron…

Trapiche emeralds are a rare variety of emerald that exhibit a six-sided, zoned morphology. Inclusions of their black shale matrix separate the growth sectors of the crystal. (See accompanying photo.) A cross-section through the trapiche crystals, cut perpendicular to the c-axis of their central core, resembles a wheel with six spokes. Trapiche emeralds are occasionally…

Very few emeralds have been mined in the United States. North Carolina has been a sporadic producer of emeralds in small quantities from a few tiny mines since the late 1800s. The Crabtree Emerald Mine was once operated by Tiffany and Company and a series of property owners between 1894 and the 1990s. Many fine clear emeralds…

Beryl is a rare mineral with a chemical composition of Be3Al2(SiO3)6. It is rare because beryllium is an element that occurs in very small amounts in the Earth’s crust. It is unusual for enough beryllium to be present in one location to form minerals. In addition, the conditions in which beryllium is present in significant amounts are…

Emerald has a Mohs hardness of 7.5 to 8, which is normally a very good hardness for jewelry use. However, most emeralds contain numerous inclusions or surface-reaching fractures. These can weaken the gem, cause it to be brittle, and make it subject to breakage. These are expected characteristics of emerald. It is rare to find an emerald that does…

By definition, emeralds are gem-quality specimens of the beryl mineral family with a rich, distinctly green color. Because of that, it is inappropriate to use the name “emerald” when marketing a beryl of any other color. The Federal Trade Commission publishes a set of Guides for the Jewelry, Precious Metals and Pewter Industries. They use “yellow…

Beryl, the mineral of which emerald is a variety, has a chemical composition of Be3Al2(SiO3)6. When pure, beryl is colorless and known as “goshenite.” Trace amounts of chromium or vanadium in the mineral cause it to develop a green color. Trace amounts of iron will tint emerald a bluish green or a yellowish green color depending upon its oxidation…

Emeralds are gem-quality specimens of the beryl mineral family with a rich, distinctly green color. They are found in igneous, metamorphic, and sedimentary rocks in a small number of locations worldwide. For over 5000 years, emeralds have been one of the most desirable and valuable colored stones. Ancient civilizations in Africa, Asia, and South America independently discovered emeralds and made them a gemstone of highest esteem. In the United…