CHROME TOURMALINE
Tourmaline is a group of complex boron cyclosilicate minerals compounded with aluminum, iron, magnesium, lithium, sodium or potasium ((Ca,K,Na)(Al,Fe,Li,Mg,Mn)3(Al,Cr,Fe,V)6(BO3)(SiO3)6(OH,F)4). They all have the same crystal structure, but with a different complex mixture of other elements, resulting in different chemical and physical properties. Tourmaline's main species include Elbaite, Liddicoatite, Dravite, Uvite and Schorl.
Chrome tourmaline is a variety of Dravite tourmaline. Its chrome-green color is one of the most beautiful colors of tourmaline. Chrome tourmaline is a rare, emerald‑green gemstone, which in recent years has become, together with Paraiba tourmaline, the most important and sought after tourmaline in the trade. Sizes over one carat are scarce and ones with fine quality are extremely rare.
LEGEND AND LORE
Tourmaline is the birthstone for the month of October and the gemstone representing the eighth wedding anniversary.
It promotes self-confidence, inspires creativity and attracts compassion, tolerance and prosperity. Tourmaline enhances balance between body and mind. It is believed to protect the wearer against bad decisions, dangers, and misfortune. It is the gemstone of love and of friendship, rendering them firm and long-lasting.
CHROME TOURMALINE COLORS
Chrome tourmaline colors range from yellowish Green to very strongly bluish Green. The chrome tourmaline color is more highly saturated than the iron bearing Green tourmaline. The color is due to trace amounts of chromium and vanadium.
CHROME TOURMALINE SOURCES
The main sources for chrome tourmaline are Tanzania and Kenya in East Africa.
PHYSICAL PROPERTIES
Variety: Chrome Tourmaline
Species/Series: Dravite Tourmaline
Chemical Composition: Sodium magnesium aluminum boron cyclosilicate (NaMg3Al6(SiO3)6(BO3)3(OH)3(OH))
Crystal System: HexagonalColor:yellowish Green to very strongly bluish Green
Hardness: 7.0 to 7.5
Refractive Index: 1.624 to 1.644 (+0.011/-0.009)
Specific Gravity: 3.06 (+0.20/-0.06)
For information on other Tourmaline varieties, select Tourmaline in the Gem Type field.
Properties RI 1.624-1.644 HARDNESS 7-7.5 SPECIFIC GRAVITY 3.06 SPECIES-TOURMALINE OPTIC CHARACTER-DR PHENOMENA-CHATOYANCY (CAT
Reactions: Ultrasonic: risky Steamer: risky Heat: fair-poor;may cause color change Chemicals: none
Major Sources: Kenya, Tanzania, Madagascar
Grading Information: GEM, AAA, AA, A+, A, B
Enhancement Code: None
Specific Gravity: 3.05
Source: 