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The Best and Most Comprehensive Guide to Sapphires in Los Angeles and on the Web!

1.   Index
2.   What Makes the Sapphire so fancy?
3.   Top Quality Sapphires are Rare
4.   The Sapphire Crystal
5.   Refractive Index & Colors
6.   Enhancements
7.   Pink Sapphires
8.   Yellow Sapphires
9.   Padparadscha Sapphires
10. Star Sapphires and Cabochons

Refractive Index

Because crystalline materials of different molecular compositions have very different interaction with incident light, the refractive index (a measure of how light is bent and its components separated as it travels through the material) is one of the most indicative properties of any given gem material, and therefore can serve as a "finger print" for its identification.

Colors

Corundum (sapphires) specimens come in a wide variety of different colors. These colors are caused by different types and levels of trace mineral compounds, which are gradually locked into the crystals during its slow formation process deep within the earth. A chemically pure sapphire crystal would be colorless.

Conventionally, blue corundum is known as blue sapphire whereas pink corundum is known as pink sapphire, and yellow corundum as yellow sapphire. An exception to this naming convention is the red corundum, which is universally known as the ruby!