2.50CT Natural Tourmaline Stone

Weight:(2.50)CT

Stone:(Tourmaline)

Scientifically, tourmaline is not a single mineral, but a group of complex crystal silicate mineral compounded with elements such as aluminum, iron, magnesium, sodium, lithium, or potassium. Tourmaline can be found in a wide variety of colors from colorless to black. This, makes tourmaline one of the most popular gems among collectors. Iron-rich tourmalines vary from black to deep brown, magnesium-rich varieties are brown to yellow, and lithium-rich tourmalines are almost any color: blue, green, red, yellow, and pink. Until recently there was no pure yellow in the rich tourmaline color spectrum. Most have a tinge of brown to them. A new vivid yellow variety, known as canary tourmaline, was found in the year 2000 in southern East Africa, in Malawi. Least valuable tourmalines are the colorless variety which is also considered as the rarest variety. Tourmaline crystals with only one color are fairly rare; tourmalines are usually bi-colour or multi-colour. Tourmaline is a typical representative of the plutonic rocks, in which are stored the volatile materials vital to its formation. However, only the black tourmalines originate from pegmatitic melts; the gem qualities are of hydrothermal origin. Common inclusions in tourmaline are cracks that run parallel to each other at 90 degrees to the length of the crystal. Thornlike fluid inclusions are another common types of inclusions that occur in tourmaline gemstone. The only acceptable type of inclusions are the tubes, that when densely packed, produce a chatoyancy and catseye effect in cabochons (the eye in catseye tourmaline can be very strong.