A popular precious gem, Ruby is the red variety of the mineral corundum—sister to blue Sapphire. Second only to Diamonds in hardness, Rubies range in shade from pink-tinted to orange‐toned to nearly brown, and of course, the rich, bright red we most often associate with this fine gem. The most sought‐after shade of Ruby is called “pigeon’s blood” and has a slight blue tint. All Rubies, however, show pleochrism: the color shifts slightly when viewed from different angles. Some Rubies fluoresce, or show fluorescent properties. Because of their magical color and timeless beauty, Rubies have been found in royal jewelry through the ages. In modern times, Ruby is the birthstone of July and the official stone of 15th and 40th anniversaries.