OVERVIEW
Color Is The Most Important Quality Factor For Ruby
The finest ruby has a pure, vibrant red to slightly purplish red color. As the color becomes too orangy or more purplish, the ruby moves down in quality. The highest-quality rubies have vivid color saturation. The color must be neither too dark nor too light to be considered finest quality.
Diamonds and Diamond Grading - Online
Diamond Essentials - eLearning
Birthstones & Anniversaries
Ruby is the birthstone for July and the gem for the 15th and 40th anniversaries.
Ratnaraj
In Sanskrit, ruby is ratnaraj, meaning the king of gems.
Cleopatra
The pharaoh known for her passion for emeralds. (So is Elizabeth Taylor, who played her in 1963.)
$6,578,500
2011 sales price for Elizabeth Taylor's emerald pendant, a record $280,000 per carat
Gem Facts
- Mineral: Beryl
- Chemical composition: Be3A12Si6O18
- Color: Vibrant green
- Refractive Index: 1.577 to 1.583
- Birefringence: 0.005 to 0.009
- Specific Gravity: 2.72 (+0.18, -0.05)
- Mohs Hardness: 7.5 to 8
Treatments
There are a number of processes used to alter the color, apparent clarity, or improve the durability of gems.
Synthetics
Some gemstones have synthetic counterparts which have essentially the same chemical, physical, and optical properties, but are grown by man in a laboratory.
Imitations
Any gem can be imitated—sometimes by manmade materials or by natural materials chosen by man to impersonate a particular gem.
Why We Love This Gem
Three Phase Inclusions
Three-phase inclusions in Colombian emeralds contain tiny crystals of rock salt, liquid, and a bubble of gas.
Quality Factors
Emerald has been the standard for green colored stones for millennia.
Cut
Rubies are commonly fashioned as mixed cuts, which have brilliant-cut crowns and step-cut pavilions.
Cut
Due to the crystal shape emeralds are commonly cut as rectangular step cuts called emerald cuts.
Research
Explore sources, gemological research, and the role of gems in history.
Recommended Reading
Amethyst Uruguay: two centuries of amethyst mining
Leo P. Kendall
