Saturation is the strength or purity of a gem's color, from grayish or brownish to vivid.
In more detail
Strong saturation is preferred in ruby, sapphire and emerald. Brownish tints lower the value of amethyst sharply. Padparadscha is the exception: its definition asks for low to medium saturation.
Related terms
- 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.
- Tone: Tone is how light or dark a gem's color is, from very light to very dark.
- Padparadscha: Padparadscha is a sapphire of soft pinkish orange to orangey pink. Its tones are pastel and its saturation low to medium.
- 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.