What is the green gem set on the old silver wire?

The gem set in the old silver wire is emerald. Emerald, known as the king of emeralds, is a very precious gem, also known as the birthstone of May, and one of the four precious gems recognized by the international jewelry industry. Because of its green color, * * *, and the unique charm of strange legends, it is deeply loved by westerners, and recently it has been increasingly loved by China people.