Rocks Vintage Collection Antique Diamond and Emerald Ring Columbian Emerald Emerald is a specimen of the mineral bery, it is the most valuable beryl. Emerald is the birthstone for May. Emerald is a medium or darker green to blue-green color gemstone. Colombian rough emeralds are known for the highest quality. These emeralds have a warmer and intense pure green color. Deep green emeralds are a rare occurrence in nature, hence are highly prized and sought after. Emerald deposits are found globally through more abundantly in some countries. Emerald Carat: 3.25ct Diamond Carat: 4.50ct approx