Ruby is one of the most popular traditional jewelry gems and can command the highest per-carat price of any colored gemstone.

The word "ruby" comes from the Latin "rubens," which means red. Rubies are found in many shades of red, from rich darkish-red to pigeon blood red and pinkish red. A fine ruby glows intense red in sunlight thanks to fluorescence, which intensifies its red color.

Rubies are commonly treated to improve both the color and clarity of the gem. Untreated rubies with high clarity are exceptionally rare and are sought after by collectors.