SAPPHIRE he name “sapphire” can also apply to any corundum that’s not ruby red, another corundum variety.
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.
- Mineral: Corundum
- Chemistry: Al2O3
- Color: Every color but red
- Refractive index: 1.762 to 1.770
- Birefringence: 0.008 to 0.010
- Specific gravity: 4.00
- Mohs Hardness: 9
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.