Rockhounding has become pretty popular in America. I would call it a safe bet that everyone at least knows a die hard rockhound - if they aren't one themselves. There is unquestionably something very special about gems that you find yourself. Ever wonder where it all started for Us in the USA? In 1820 tourmaline was discovered by Elijah Hamilin and Ezekiel Homes at Mount Mica, Maine. By 1822 America had it's first gemstone mine. It is hard to imagine another gem being so right to represent the avent of America's love of gem hunting. Having a hardness of 7.5, tourmaline makes easily workable gem faciting material. It also comes in every color and hue imaginable. Many crystals contain several colors within one stone, the "watermelon" stone with it's pink center and green outer layers being the most well known. Buergerite, elbaite, schrol, utive, foitite dravite, povondravite, chromdravite, feruvite aliddicoatite, olenite are all mineral species of tourmaline, making 11 mineral species in all. Tourmaline produces some sizable crystals, the usual range falling from under an inch long to over a foot long and several inches wide. Needless to say many spectacular huge gems, a 400 carate pink/red stone, 256 carate blue/green, a 75 pound green/pink to name a just a few, have been cut from large tourmaline crystals, and many of the large cut gems are flawless -- and spectacular. Cutting gemstones is not the only value of tourmaline, however. It is also used to make a polarizing apparatus (tourmaline tongs), pressure measuring equipment, and specialist microphones. Scientists can use tourmaline to gain knowledge of the geological past for the area in which the crystals are found. In the United States tourmaline can be found in abundance in southern California, Connecticut, Maine, New York and Texas. It has also been found in Idaho, South Dakota, North Carolina, and a few other states in lesser quantities. Worldwide, tourmaline is found in Africa, Brazil, Madagascar, Mexico, Myanmar, Namibia, Sri Lanka, and The Isle of Elba. Identifying factors for those hunting tourmaline are: Color - from transparent to black, often multi-colored
Luster - vitreous to resinous
Streak - uncolored
Cleavage - none
Fracture - variable
Specific Gravity - 3.0 - 3.2
Chemistry - SiO2 + B, Al
Crystal System - hexagonal
Hardness - 7.0 - 7.5 Click the URL below to see some great examples of tourmaline crystals: http://www.buenavistagemworks.com/tourmaline/tourmphoto1.htm |
