The chemical composition of tourmaline

Tourmaline is a gem tourmaline, collectively, its mineral name comes from the mineral tourmaline thermoelectric properties. 18th century, the Dutch discovered tourmaline has a function to absorb dust, confetti in the sunlight, named for the "suck limestone." English name is the ancient Sinhalese "Turmali" is derived, means "mineral was mixed color." Tourmaline bright colors, colorful, can stimulate people's artistic inspiration, expressing complex emotion, with opal together as October birthday stone, a symbol of peace and hope. The basic nature of the chemical composition of tourmaline. Tourmaline formula can be abbreviated as NaR3Al6 [Si6O18] [BO3] 3 (OH, F) 4, the chemical composition of complex class quality structure with alternatives like wide, where Na + may locally K + and Ca2 + in place; R is mainly Mg2, Fe2 + , Li +, Al3 +, was between classes they isomorphic substitution. It was Mg2 and Fe2 +, Li + and Al3 + entirely between isomorphic substitution, and Mg2 + and Li +, Al3 + substitution between is limited. Thus the mineralogy is divided magnesium tourmaline, iron tourmaline and lithium tourmaline three main end-member types, but also as Tourmaline. Tourmaline is often the type of transition for these subspecies end members between components. When the composition of iron long, dark, rarely achieved gem. Reprinted: http: //www.shunxin1688.com/shownews.asp id = 287?