Desert Messenger

April 20, 2016 www.DesertMessenger.com 15 In the ancient, arid lands across the desert southwest, Persia and the Far East, the people danced and rejoiced when the rains came. Na- tive American legend says that their tears of joy mixed with the rain and air from the sky and seeped into Mother Earth to join with the miner- als and become the Fallen SkyStone. Native Americans had as many dif- ferent words for this stone as there were languages spoken, but most of them translated into English as some variation of "sky stone." The sky stone is a hydrous copper aluminum phosphate that typically forms in arid climates, and we know it today as turquoise. Turquoise forms one tiny crystal at a time, as water seeps through a host rock and interacts slowly over thousands or millions of years with a very special chemistry of copper, iron, phospho- rous, and aluminum. Other minerals in the deposit or the host rock pro- duce the variations in color, hard- ness, and matrix that can be found within the gemstone. The unique chemical combination and process by which turquoise is formed is even more rare than the geological pro- cess that forms diamonds. Deposits of turquoise have been found in the Southwest United States, the Middle East, the Far East, Chile, and Mexico. Turquoise has been prized for thousands of years by cultures around the world for its beauty and reputed spiritual qualities. In the ancient Far East- ern regions of Tibet and China, turquoise was mined and highly sought after since earliest times as By Jenn Jedidiah Free for RocksInMyHead™ It's a special kind of chemistry a stone of royalty and wealth. In the Middle East, Egyptians were mining and creating jewelry from turquoise 7000 years ago, and in Persia it was mined since before 2100BC. For centuries, the Middle East supplied the stone to the Greeks, Romans and European cultures by way of Turkish traders. In fact, our modern name "turquoise" is derived from the French word for "Turkish stone." Here in North America, Na- tive Americans had been min- ing "sky stone" for centuries be- fore the arrival of the Europe- ans. The oldest known source of turquoise in the desert southwest is what is known today as the Cer- rillos Mining District in New Mexi- co. In fact, this is the oldest mine of any kind on the North Ameri- can Continent and dates back over 2000 years. Turquoise mined from this area has been found in Chaco Canyon and as far away as Oaxaca, Mexico where it was traded with the Aztecs and Mayans. Chaco Canyon turquoise has been found carved into beads or animal fetishes, used as inlay on wood, bone, and shell or- naments, and as amulets set in gold adorning the crowns of Aztec and Mixtec Kings. There are two types of turquoise formations: Vein and Nugget. Vein Turquoise forms as a solution fi lling cracks, called fi ssures, in the host rock. Most vein Turquoise is free of matrix, though on rare occasions, vein Turquoise can contain matrix. ADVENTURES WITH ROCKS ™ Nugget Turquoise is formed as the Turquoise collects in small pockets and holes within clay-fi lled fi ssures. Commonly, nuggets will have a thin, evenly-spaced "spider-web" type matrix, though occasionally they will be clear of matrix. Matrix color is determined by the host rock in which the Turquoise formed. Matrix can be reddish or rust-col- ored, brown, black, golden colored, or even silvery-gray. Brown or red- dish matrix is the result of iron ox- ides in the rock, while black matrix typically is caused by iron pyrite within the host rock. The colors of Turquoise also vary greatly and are determined in part by minerals present in the host rock. Colors can often vary even within the same mine. Ex- cess amounts of copper p r o d u c e blue, while a l u m i n u m produces a T u r q u o i s e more in the green range. Zinc and zinc oxides yield a yellow-green or a bright green called apple green. Most Turquoise mined in Arizona and New Mexico is in the blue range because of the abundance of copper here. Nevada produces many fi ne examples of green and yellow-green Turquoise. Natural Turquoise is a soft, some- what porous stone with a hardness of 5. Only about 10% of mined Tur- quoise can be used without some sort of treatment, though this can vary somewhat from mine to mine. Without treatment, most Turquoise will absorb chemicals from its envi- ronment and over time will change to a greenish color, crack, and chip. Native peoples have been treating Turquoise for thousands of years us- ing animal fats and paraffi n waxes. Today gem grade Turquoise stones are impregnated with a liquid resin or silica. This treatment, called sta- bilizing or enhancing, adds a new material to the stone but does not change the actual chemical struc- ture. Stabilization processes or for- mulas are unique to each mine - a specifi c process developed specially by that mine to suit its Turquoise similar to a distinctive recipe or specialty belonging to a restaurant. Often a particular mine's stabiliza- tion process is a closely guarded trade secret that has been handed down through generations. Other less desirable types of Tur- quoise are color-treated or reconsti- tuted. The process of color-treat- ment involves adding dye and resin to a chalky stone to enhance its hard- ness and color. This is also known as color-enhanced or color-infused, and is best recognized by a translu- cent plastic-type appearance and un- natural color. Reconstituted Tur- quoise consists of Turquoise powder and chips mixed with resins, coloring agents and compressed into a bar or loaf. Simulated Turquoise, on the other hand is plastic that is colored with pigments to resemble Turquoise and then pressed or molded into blocks. While it is often cut, polished, and made into jewelry, this material contains no actual Turquoise and has a very "plastic-y" look and feel. Another simulated Turquoise is the white stone howlite which is dyed to look like Turquoise. If you're traveling in the Kingman, AZ, area this summer, be sure to stop at the Colbaugh turquoise shop just off of highway 93. The Colbaugh family has been mining Kingman Turquoise since the 1970s. If you are not in the Kingman area, we carry a great selection of Arizona Turquoise from the Kingman and Sleeping Beauty Mines, Nevada Turquoise from Carico Lake in Lander County, and turquoise from New Mexico. Visit us online at RocksInMyHead. com, or you can order by phone at 605-376-8754 or email. We will be open again in Quartzsite at Rice Ranch A37 beginning in November. Meanwhile, have a great summer!

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