A trade color term is a market name for a fine color, such as pigeon's blood, royal blue or cornflower. It is not a gemological standard.
In more detail
No universally accepted definitions exist for these terms. Each lab that uses one sets its own criteria. So the same stone can get the term from one lab and not from another. Read which lab issued the term, and on what criteria.
On a grading report
Some labs add it as a separate color statement or appendix, not as the variety name.
Related terms
- Pigeon's blood: Pigeon's blood is a trade name for a ruby of intense, saturated, even red. It has no single agreed standard.
- Royal blue: Royal blue is a trade name for a sapphire of intense, saturated, even blue. It is not a single agreed standard.
- Kashmir sapphire: A Kashmir sapphire is a blue sapphire from the Kashmir region on the India/Pakistan border. 'Kashmir blue' is a trade name for a deep, velvety blue, with no single agreed standard.
- Padparadscha: Padparadscha is a sapphire of soft pinkish orange to orangey pink. Its tones are pastel and its saturation low to medium.
- Hue: Hue is the basic color of a gem, such as red, blue or green. A second color can modify it, as in purplish red.