Colombia is known for offering the highest quality emeralds. This is because the stones from there have a high transparency and a light green tint. This different color of the stone is determined by its origin.
This is because each place has the presence of different substances and in different quantities as well. So what gives the emeralds so unique color is the presence of chromium, iron and vanadium. Because of these differences the colors of the stones in each region are different from each other. The Colombian emerald is known for its unique color.