Sapphire: History's Most Famous Blue Gemstone

Throughout history, sapphire, September's birthstone, has been considered the ultimate blue gemstone. This regal stone is so valued, it is actually the recommended gem for couples celebrating both their fifth and 45th anniversaries.

Although sapphire, a variety of corundum, is most valued in deep blue, the stone comes in a variety of hues, including pink, green, orange, yellow, purple, gray, black, brown, and colorless. Some sapphires even display a six-rayed star pattern when cut into cabochons (domed, unfaceted stones) and are appropriately called star sapphires. The only color you won't find a sapphire in is red -- the red variety of corundum is called ruby.

The word sapphire has roots in several languages: the Arabs called the stone "safir"; the Romans called it "sapphirus" (meaning blue); and the Greeks called it "sappheiros" after the island of sappherine in the Arabian Sea where sapphires were found at that time.

During the Middle Ages, sapphire was thought to represent purity of the soul. It was believed that the stone's color would darken if worn by an "impure" or wicked person. Sapphire was also considered the "Oracle's Stone" and was used to safeguard and foretell the future. The ancients believed the Ten Commandments were written on a sapphire tablet.

The world's finest sapphires used to come from Kashmir, India, but the mines there are now considered depleted. Stones from this region are characterized by their deep cornflower blue color and silky sheen. Incomparable sapphires were dug from one legendary ancient Kashmire mine, but its location is lost in the mists of time -- thus adding to the stones' mystique. Current important sapphire-producing locales include Australia, Myanmar (Burma), Sri Lanka and Thailand. Sapphires also can be found in Cambodia, China, Kenya, Nigeria, Tanzania and the United States (primarily in Montana). Large sapphires are quite rare, and are often given names such as with notable diamonds. Two of the most famous sapphires are part of the British Crown Jewels in the Tower of London. The St. Edwards Sapphire is a rose-cut gem of unknown size set in the finial cross of the Imperial Crown. It derives its name from Edward the Confessor, who wore the stone on a ring during his coronation in 1042. The Stuart Sapphire is a 104-carat oval mounted on the band at the rear of the Imperial Crown. Another famous sapphire associated with British royalty is the one that Prince Charles presented to Princess Diana to seal their engagement. The oval blue, 18-carat sapphire is surrounded by diamonds and set in sterling silver.

Here are a few of history's other notable sapphires. Many are on display in museums and private collections around the world: