Difference between revisions of "Tourmaline"

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[[Image:Green-tourmaline.JPG|left|framed|Green toumaline]]<br clear="left" />
 
Tourmaline is an extremely complex borosilicate that occurs in more than 100 colors. It is hard and durable and very well suited for jewelry. It is a pyroelectric mineral, meaning that when warmed, it attracts dust and other lightweight particles. It wasn't introduced into Europe until the early 1700's, when it was imported from the east. Shortly thereafter it was declared a stone of the Muses, inspiring and enriching the creative processes. It was a talisman for artists, actors and writers. Today,it is mined extensively in South America, East Africa and in Southern California. <br>
 
Tourmaline is an extremely complex borosilicate that occurs in more than 100 colors. It is hard and durable and very well suited for jewelry. It is a pyroelectric mineral, meaning that when warmed, it attracts dust and other lightweight particles. It wasn't introduced into Europe until the early 1700's, when it was imported from the east. Shortly thereafter it was declared a stone of the Muses, inspiring and enriching the creative processes. It was a talisman for artists, actors and writers. Today,it is mined extensively in South America, East Africa and in Southern California. <br>
 
'''Tourmaline Family:'''<br>
 
'''Tourmaline Family:'''<br>

Revision as of 09:24, 11 December 2006

Tourmaline
Chemical composition Complex borosilicate
Crystal system Trigonal
Habit Trigonal prisms with convex faces
Fracture Conchoidal
Hardness 7.5
Optic nature Uniaxial -
Refractive index 1.62 - 1.64
Birefringence 0.014-0.021 (up to 0.039)
Dispersion Low, 0.018
Specific gravity 3.06 (3.01-3.11)
Lustre Vitreous
Pleochroism Weak to strong
Green toumaline

Tourmaline is an extremely complex borosilicate that occurs in more than 100 colors. It is hard and durable and very well suited for jewelry. It is a pyroelectric mineral, meaning that when warmed, it attracts dust and other lightweight particles. It wasn't introduced into Europe until the early 1700's, when it was imported from the east. Shortly thereafter it was declared a stone of the Muses, inspiring and enriching the creative processes. It was a talisman for artists, actors and writers. Today,it is mined extensively in South America, East Africa and in Southern California.
Tourmaline Family:
Paraiba Tourmaline
Rubellite Tourmaline
Indicolite Tourmaline
Verdite Tourmaline
Dravite Tourmaline
Achroite Tourmaline
Chrome Tourmaline
Bicolor Tourmaline
Tricolor Tourmaline
Watermelon Tourmaline
Schorl Tourmaline