"emerald" の定義と意味

What is an "emerald"?

An emerald is a precious green gemstone that belongs to the beryl mineral family, which also includes aquamarine and morganite. Its green color is caused by the presence of chromium and vanadium impurities in the crystal. Emeralds are mined in several countries including Colombia, Zambia, Brazil, and Zimbabwe. They have been highly valued for centuries and were used by ancient Egyptians, Aztecs, and Incas in jewelry, as well as for their supposed healing and protective powers. Today, emeralds are still a popular gemstone used in a variety of jewelry designs, from rings to necklaces and bracelets. The most valuable emeralds are typically vivid green with a high degree of transparency and few visible inclusions.