This 4 carat sapphire is set in an engraved yellow gold and platinum band - click here to see more pictures of this exquisite ring

Sapphires are the most popular of the three colored precious gemstones. Similar to rubies (they are both corundum), sapphires come in many different colors, shapes and sizes. They provide a great variety to gemstone lovers and ensure the enduring popularity of sapphire jewelry. With hardness just below that of diamonds (10), sapphires (9) are one of the toughest gemstones, and with no cleavage (open flaws to the surface), breakage rarely occurs.

Sapphire and diamond earrings set in 14k yellow gold - click to enlarge

Intense medium dark blue is the most sought after color for blue sapphires. Very fine non-heat treated (to enhance color and clarity) sapphires are extremely rare and tremendously valuable. Sri Lanka, Cambodia and Burma produce very fine pure blue sapphires, although Cambodian sapphires are sometimes slightly dark. Australian sapphires are generally darker in color and can have green overtones and concentric hexagonal bands in lower qualities. Midnight blue sapphires have traditionally been looked down on but today, midnight blue sapphire jewelry is increasingly common - particularly for sapphire earrings due to their lower cost.

4.00c emerald cut fine blue Ceylon sapphire with 4.00c total weight tapered baguette diamonds F-Vs2 in a traditional ballerina platinum ring

For sapphires, like most colored stones, the following order of criteria is generally considered optimal: Color, Life or brilliance, Clarity or transparency, cut or proportions and size or carat to fit one’s budget. Intensity, uniformity and purity of color are the most important considerations when making a decision about the purchase of a blue sapphire. Fine blue sapphires should not contain any overtones or secondary colors, for this will lessen the beauty of this precious gemstone. As the overall beauty of the stone will depend on the cutting, this characteristic must always be taken into consideration. Very dark blue sapphires will appear black under low light settings, while fine blue sapphires will maintain their color in any light setting. Blue sapphire jewelry remains one of most sought after jewelry types with sapphire wedding or engagement rings greatly influence by Lady Diana’s blue Sapphire wedding ring—a fine blue oval prong set with brilliant cut diamonds.

Sapphire and diamond tennis bracelet

The island of Serendib (present day Sri Lanka) holds one of the earliest records for the mining of sapphires. Ancient people believed that the power of wisdom was contained within this precious gemstone. They believed that when the wearer of a sapphire faced challenging obstacles, the stone's power enabled them to find the correct solution. The modern word sapphire is derived from the ancient Latin term "Sapphirus."

Sapphires and diamonds are shown off in these boldly sculpted 18 karat yellow gold and platinum stackable bands - click a thumbnail to see a larger picture

Australia and Africa are the world's largest suppliers of blue sapphires. Sri Lanka also provides a large portion of the world's supply of blue sapphires. Gemstones from this island are often called "Ceylon" sapphires, which was the name of the island before it was changed to Sri Lanka. Pailin, Cambodia, is another source of exceptional blue sapphires. Burma is also known for its top quality supply of this gemstone.

Sapphires come in all spectrums of color, except for red (red corundum is called Ruby). Often when people refer to sapphires, they mean blue sapphires. Other color sapphires are referred to as fancy sapphires with pink, yellow and golden most often requested.