cobalt blue spinel

Color types such as "pigeon's blood," "Paraíba" and "cobalt blue" have become wildly popular in the gem trade. But there is a vast difference between coining such terms and applying them in a way that is both consistent and logical. Richard Hughes casts a critical eye on the subject.

Color types such as "pigeon's blood," "cobalt blue" and "Santa Maria" are wildly popular, but also wildly inconsistent.

Color types such as "pigeon's blood," "cobalt blue" and "Santa Maria" are wildly popular, but also wildly inconsistent.