Color
The color of gemstones is typically graded on three key factors: hue, tone, and saturation. Hue describes the gradation of color, such as dark or pale, while tone pertains to how much light the gemstone absorbs or reflects, affecting color intensity. Saturation measures the extent to which the stone displays the primary color. Pink sapphires are particularly valued for their varied shades, each being highly sought after.
The term sapphire comes from the Greek word “sapphirus,” meaning “blue.” However, sapphires come in many colors, including pink, yellow, orange, green, black, color-change, purple, violet, and light blue. Sapphires that are not blue, pink, yellow, green, or orange are called “natural fancy-color sapphires.” Red and pink hues come from chromium traces; higher concentrations lead to a deeper color, turning the gem into a ruby.
Pink sapphires exhibit a variety of pink hues, from powder pink to shocking pink, ceylon pink, bubblegum pink, baby blush pink, hot pink, pastel pink, and more. Lighter and darker stones tend to be less valuable. An exceptionally rare variant is the pinkish-orange padparadscha sapphire from Sri Lanka, named after the Sinhalese word for “lotus color.”
Hue, Tone & Saturation
Hue refers to the color on the color wheel spectrum. Pink sapphires are unique because their hues range from light baby blush pink to intense hot pinks. Unlike rubies, their hues do not have to conform to a specific color, offering a wide array of pink shades.
Saturation measures the color’s intensity. Medium to medium-dark pink tones with high saturation are rarer, making overly dark or light pink sapphires less valuable.
The hue and saturation of pink sapphires depend on personal preference. Some people favor a light pale pink stone, while others might prefer a hot pink one. Historically, the most desired were saturated purplish-red hues with medium tones, described as hot pink or bubblegum pink. However, lighter pink tones have recently gained popularity due to their airy nature, particularly complementing rose gold settings.
Opacity
Besides color, the opacity of pink sapphires is crucial. Stones with excessive inclusions, which make them difficult to see through, are less valuable. Pink sapphires may feature various inclusions like thin mineral needles, mineral crystals, color zoning, and color banding. In lighter pink stones, these inclusions are more noticeable.
Treatment
Treatment can enhance the color and clarity of pink sapphires, with heat treatment being the most common. Heating a pink sapphire can eliminate blue tints, resulting in a purer pink. The color achieved through heat treatment is permanent, will not fade, and is generally accepted by most retailers.
Other treatments address inclusions by filling fractures or inclusions with glass or using newer methods like titanium and beryllium treatments. Some of these newer treatments can be controversial, so understanding the types of treatments is essential.
