The name “sapphire” is derived from the Latin word “saphirus” and the Greek word “sapheiros,” both meaning blue. Some believe that the name sapphire is derived from its association with the planet Saturn.
The sapphire is a precious gemstone, corundum in the same family as the ruby. The only difference between a ruby and a sapphire is simply the color. It is typically blue, but natural "fancy" sapphires also occur in yellow, purple, orange, and green colors; "parti sapphires" show two or more colors. The only color corundum stone that the term sapphire is not used for is red, which is called a ruby. Because sapphires are available in so many colors, they are the most important and versatile of all the gemstones. Rubies and sapphires are said to be prized just under the level of diamonds because of their hardness. Diamonds are listed as a ten in terms of hardness, sapphires as a nine.
Gemstone color can be described in terms of hue, saturation, and tone. Hue is commonly understood as the “color” of the gemstone. Saturation refers to the vividness or brightness of the hue, and tone is the lightness to darkness of the hue. Blue sapphire exists in various mixtures of its primary (blue) and secondary hues, various tonal levels (shades), and at various levels of saturation (vividness).
Blue sapphire colors range from pale blue to cornflower blue (known as Kashmir sapphire), royal blue, navy blue, and midnight blue. Pink sapphires occur in shades from light to dark pink and deepen in color as the number of chromium increases. The deeper the pink color, the higher their monetary value.
Another extremely valuable sapphire form is the very rare, orange-pink Padparadscha. Padparadscha is a delicate, light to medium toned, pink-orange to orange-pink hue corundum, originally found in Sri-Lanka but also found in deposits in Vietnam and parts of East Africa. Padparadscha sapphires are rare; the rarest of all is the totally natural variety, with no sign of artificial treatment.
A rare variety of natural sapphire, known as color-change sapphire, exhibits different colors in a different light. Color change sapphires are blue in outdoor light and purple under incandescent indoor light, or green to gray-green in daylight and pink to reddish-violet in incandescent light. Color change sapphires come from a variety of locations, including Madagascar, Myanmar, Sri Lanka, and Tanzania.
A star sapphire is a type of sapphire that exhibits a star-like phenomenon known as asterism. Star sapphires contain intersecting needle-like inclusions following the underlying crystal structure that causes the appearance of a six-rayed "star"-shaped.
The main sources are United States (Montana) Cambodia, Sri Lanka (Ceylon), Burma (Myanmar), China, Madagascar, Tanzania, Australia, Colombia, Ethiopia, Kenya, Rwanda, Nigeria, Tanzania, Vietnam, and Thailand. At one time exceptional sapphires came from Kashmir, but no new material has been found there for about 100 years.
The sapphire is the birthstone for the month of September and the gem of the 5th and the 45th wedding anniversaries.