Sapphires That Change Color

Sapphires are usually known for their deep blue hue.

Sapphires are typically thought of as the deep blue stone that is the birthstone for September. It is usually as such, but sapphires also are available in many other colors. The sapphire is part of the corundum family of gems, which is supposed to be white, but various impurities cause the different colors. In addtion, there are rare sapphires that can change their color when exposed to different types of light. Natural light and artificial light will produce an appearance of different colors in these sapphires.

Color

In natural, outdoor light, color-change sapphires appear to be blue, as you might expect. However, when a color-change sapphire is taken indoors and exposed to artificial light, it appears to be purple. Variances can occur, and the stone may appear to be bluish-purple when indoors. Occasionally a color-change sapphire may appear pink in natural light and turn to green indoors. Color is the most important aspect when determining the value of a sapphire. Medium tones are considered the most valuable; stones that are too light or too dark are less desirable.

Why Do They Change Color?

Color-change sapphires can change color due to their atomic composition. Certain atoms in the gem are intensified by the presence of the ultraviolet rays of daylight, but artificial light does not produce the same effect. A strong color-change effect gives the stone a higher value than a moderate-change effect.

Where Are They Found?

Color-change sapphires are most commonly found in Tanzania, in the Umbra River Valley. A geological physical characteristic in this area, called the Mozambique Orogenic Belt, supports some of the largest gem deposits in the world.

Hardness

Color-change sapphires are very beautiful, and they also have a hardness rating of 9, making it a good, sturdy gem for any kind of jewelry from engagement rings to earrings. The gems are faceted and usually cut in the round brilliant shape, although other shapes are available as well.

Alexandrite

Alexandrite, which was discovered in 1830 in Russia, is another gem that has color-changing properties. In daylight, it is a bluish-green, but under artificial light it is a raspberry red, sometimes with purple tones. Synthetic color-change sapphires that have a green-to-red change are sometimes confused with alexandrite. As a genuine alexandrite has a much greater value than that of a synthetic color-change sapphire, care must be taken when shopping.

Folklore

For the spiritual among us, the sapphire is believed to support inner peace and to have healing qualities for maladies such as rheumatism, colic in babies and depression. It is also associated with New Age powers such as telepathy and astral projection.

References

• Minerals: The Mineral & Gemstone Kingdom: The Precious Gemstone Sapphire
• AJS Gem: Fancy-Color Change Sapphire Gemstone Information
• The Natural Sapphire Company: Sapphires from Tanzania
• Awesome Gems: Top Quality Color Change Sapphire Gemstones
• Alexandrite
• Sapphire Facts, Information and Description: Sapphire Facts, Information and Description