Black pearls are blue, which is good. Black pearl is a kind of jewelry with black as the main color, but sometimes blue or green can be seen on the surface or inside of black pearl. This associated color is called halo, which is a precious feature of black pearls. In terms of market pricing, black pearls with obvious color matching, such as those with strong halo, will have higher prices.

It should be noted that everyone's aesthetic preferences may be different. For the color and companion color of black pearls, liking is the most important.