Besides blue sapphire and ruby, the corundum family also includes so-called “fancy sapphires.” They come in violet, green, yellow, orange, pink, purple, and intermediate hues. Some stones exhibit the phenomenon known as color change, most often going from blue in daylight or fluorescent lighting to purple under incandescent light. Sapphires can even be gray, black, or brown.
Birthstones & Anniversaries
Sapphire is the birthstone for September and the gem of the 5th and 45th anniversaries.
Intensely saturated and velvety, rare sapphires from Kashmir set the standard for blue.
The world’s most famous engagement ring: Kate Middleton’s and Princess Diana’s sapphire.
A rare and valuable pinkish-orange sapphire named from the Sinhalese for lotus blossom.
Every color but red
1.762 to 1.770
0.008 to 0.010
There are a number of processes used to alter the color, apparent clarity, or improve the durability of gems.Learn More
Some gemstones have synthetic counterparts that have essentially the same chemical, physical, and optical properties, but are grown by man in a laboratory.Learn More
Any gem can be imitated—sometimes by manmade materials or by natural materials chosen by man to impersonate a particular gem.Learn More
Why We Love This Gemstone
Vivid And Saturated
Sapphire’s blue can be vivid and saturated, like it’s lit from within.
It’s so durable, synthetic sapphire is used for the windows of supermarket scanners and spacecraft.
Sapphire often contains delicate intersecting needles of rutile that gemologists call silk.
Each color of sapphire has its own quality variations.
Sapphires come in a variety of colors. Preferred sapphires have strong to vivid color saturation, regardless of hue.
Blue sapphires typically have some inclusions, but they generally have better clarity than rubies.
Sapphire is often cut with a brilliant pattern on the crown and a step cut pattern on the pavilion.
Blue sapphires range in size, and large blue sapphires are more readily available than large rubies.
Sapphire Quality Factors: The Comprehensive Guide
Explore sources, gemological research, and the role of gems in history.
Gemological Characterization of Sapphires from Yogo Gulch, MontanaNathan D. Renfro, Aaron C. Palke, and Richard B. Berg , Aug 6, 2018 Read Article
The Role of Silicon in the Color of Gem CorundumJohn L. Emmett, Jennifer Stone-Sundberg, Yunbin Guan, and Ziyin Sun , May 7, 2017 Read Article
Big Sky Country Sapphire: Visiting Montana’s Alluvial DepositsTao Hsu, Andrew Lucas, Robert E. Kane, Shane McClure, and Nathan Renfro , Aug 7, 2017 Read Article
The Book of Ruby and Sapphire
J. F. Halford-Walkins
Ruby & Sapphire
Sapphires in the Butte-Deer Lodge area, Montana
Richard B. Berg