For centuries tourmalines have adorned the jewels of royalty. The Empress Dowager Tz'u Hsi, the last empress of China, valued the rich pink colors above all other gemstones. The people of ancient Ceylon called tourmaline "turmali," the Sinhalese word for "more colors." Perhaps this is why ancient mystics believed tourmaline could encourage artistic intuition: it has the palette to express every mood.
Vivid reds, hot pinks, verdant greens and blues abound in this marvelous gem variety. Earth tones as varied as a prairie sunset are readily available. Not only does tourmaline occur in a spectacular range of colors, but it also combines those colors in a single gemstone called "bi-color" or "parti-color" tourmaline. One color combination with a pink center and a green outer rim is called "watermelon" tourmaline, and is cut in thin slices similar to its namesake. More information on Tourmaline can be found here. 
FACTS
MINERAL: Tourmaline
CHEMISTRY: 
Elbaite Na(Li1.5,Al1.5)Al6Si6O18(BO3)3(OH)4
Dravite NaMg3Al6Si6O18(BO3)3(OH)4
Liddicoatite Ca(Li2Al)Al6Si6O18(BO3)3(OH)3F
Chromedravite NaMg3Cr6Si6O18(BO3)3(OH)4
COLOR: All colors
REFRACTIVE INDEX: 1.624 to 1.644
BIREFRINGENCE: 0.018 to 0.040
SPECIFIC GRAVITY: 3.06 (+0.20, -0.06)
MOHS HARDNESS: 7 to 7.5
-Source AGTA, GIA
$118.15
$6,162.00
$6,900.00
$178.50
$198.05
$215.90
$216.75
$1,782.00
$2,515.00
$2,895.00
$256.00
$2,007.00
$4,340.00
$1,436.50
$2,300.00
$363.00
$675.00
$8,166.00
$18,198.00