The gemstone, Ruby, has been called the king of precious gemstones for its rarity, hardness (second only to diamond), beauty, and seemingly mystical powers. Long associated with the life force blood, ruby was a symbol of power and youthful energy in Indian jewelry. Ruby is the red variety of the mineral corundum, colored by the element chromium. All other colors of gem-quality corundum are called sapphire, which means color is key for this royal gemstone.
In addition to being the July birthstone, ruby is traditionally given for the 15th and 40th wedding anniversaries.