Tuesday, June 18, 2013

Turquoise

Turquoise Pebble
Turquoise (my favorite color!) is a semi-precious stone, actually a mineral,  that is so well-known that it has a color named after it!  It is a soft stone, that ranges in color from green to bluish green to greenish blue!  The word "turquoise" is French, meaning "Turkish" because Turkey is where the stone was "found" in the 16th Century, although the stone has been treasured for thousands of years as a holy stone, a bringer of good luck, and a talisman!  Since the First Dynasty (3000 BC) and possibly before that,  turquoise was mined in the Sinai Peninsula and used by the Egyptians.

Turquoise is fragile, with a hardness of 6, which is slightly harder than window glass!  The blue is attributed to the presence of copper and the green is attributable to the presence of iron.  It may be peppered with flecks of iron pyrite (Fool's Gold) or containing dark veins of limonite. Turquoise is primarily found in arid regions and primarily forms in cavities in volcanic rock. 
Persian Turquoise and Topaz Pendant

Persia (now known as Iran) mined Turquoise for several thousand years and is still an important source of very high-quality turquoise.  Domes of Persian palaces were covered with the beautiful blue Persian Turquoise because the intense color symbolized heaven on earth!  I actually have a beautiful authentic Persian turquoise pendant (with blue topaz) in my etsy shop.  You can click on the picture (see right) which will take you to the lovely pendant in my shop.  This is REAL turquoise which I took to Rio Grande Jewelry Supply (a very reputable jewelers' supply company, which is nearby) who verified its authenticity. 


Treated Turquoise

First, it should be noted that turquoise has been treated for thousands of years!  Oiling and waxing turquoise were common in ancient times. to protect the stone and bring out the beautiful blues and greens.

Today, almost ALL of the turquoise on the market has been treated in some way to correct two problems with turquoise: it is soft, and it is porous, which means its susceptible to staining, fracturing, discoloring, crumbling, and fading.  No joke, about 97% (or more) of ALL genuine turquoise is treated in some way---and there is NOTHING wrong with that.  People will say, "Oh, I only buy natural turquoise..." and the thing is, natural turquoise must be treated since the stone is so soft it would crumble or break otherwise, or so porous that it will absorb skin oils and constantly comes in contact with other elements.  In addition, many mines are depleted and very low quality turquoise is left.  What can be done?

Enhanced Turquoise:  Also known as the Zachary or Foutz Method, this involves impregnating the turquoise with vaporized quartz.  This makes the stone harder and enhances the color.  This is difficult to detect because quartz is naturally found in some turquoise.

Stabilized Turquoise:  Stabilization is like a modern-day version of waxing or oiling, using better methods.  Stabilization not only protects the stone, but also reduces the chances of fracturing.  Turquoise might be soaked for an extended period of time in a solution, such as epoxy or plastic or resin.  Newer methods use high pressure systems to impregnate the minute cracks in the turquoise with a hardening solution very quickly.  The turquoise stones are then cut and polished, resulting in a shiny and smooth turquoise gem.  This is a common and practical solution in the turquoise jewelry industry.  Stabilized turquoise is real turquoise that has been treated to harden the stone so it's suitable for jewelry.  Stabilized does NOT necessarily mean dyed!  Over 97% of natural turquoise has been stabilized.  If you want undyed turquoise, you need to ask the seller! 

Wax Treated:  Most turquoise from China is wax treated, but on the surface only.  The paraffin treatment enhances the color.

Color Treatments:  Much of the stabilized turquoise is also dyed which brings it to the "Persian Blue" that everyone wants.  Another type of dying involves enhancing the matrix (the dark veining).  Much dyed turquoise is sold as "natural" in the marketplace, sadly.  Color enhancements should always be divulged to the consumer, but that isn't always done.

Reconstituted Turquoise:  Also known as "stovetop turquoise", this method involves taking powdered low-quality turquoise (smashing it into a powder), mixing it with a binding agent and dyes, pouring it into molds, and drying it.  The result is a block of turquoise which is cut into slabs and sold.  This is different than "block turquoise" (see below).

Block Turquoise (Fake)
Block Turquoise:  completed artificial, total imitation, no turquoise whatsoever (not even powdered turquoise), just simply plastic, fake turquoise which shouldn't even use the name "turquoise" at all.  Block turquoise is used heavily in inlay and heishi products.

Turquoise Doublets:  sometimes, very thin veins of turquoise are found that are too thin to be made into jewelry.  These slender pieces of turquoise are then glued to a base consisting of stone or another material for added strength, then cut, shaped and polished.  Sometimes a thin vein of turquoise can be cut with its host stone serving as the supportive base.  This allows for a beautiful, genuine piece of turquoise to be incorporated into jewelry----as long as the consumer is informed that this is a doublet and not a solid piece of turquoise.

Mosaic "Turquoise" firemountaingems.com
Mosaic Turquoise:  This is becoming popular lately, but what is it?  It is actually pieces of magnesite or chalk turquoise that is dyed and held together with plastics, cut and polished, with a result that looks interesting and colorful.  It's not turquoise at all--just pieces of simulated turquoise, glued together.

Dyed Magnesite 
Dyed Stones and Other Materials:  A lot of naturally occurring stones  look similar to turquoise when they are dyed blue. These include Howlite---a white rock with black or gray markings, and Magnite or Magnesite---a chalky white mineral that forms in rough nodules looking a bit like cauliflower. Other simulations include glass, plastic, faience ceramic and polymer clay.

What is White Turquoise? Purple Turquoise?  Turquoise is always blue-green, green-blue or green.  White turquoise is howlite, or magnesite.  Purple Turquoise is probably sugilite, or dyed howlite, or possibly a composite turquoise (pieces of real turquoise) mixed with a dyed resin (in purple, vibrant green, red, all kinds of colors).  Turquoise is a stone AND a color for a reason--the color describes the stone, and the stone describes the color.  (Sort of like calling something a "green ruby", or "purple emerald", it makes no sense.)
White dyed magnesite, howlite,white quartzite, dyed mother of pearl

There are a couple of mines in Arizona and Nevada that are marketing some white material as "White Buffalo Turquoise".   Actually, they are calling it simply "White Buffalo" because it's really not turquoise, although very small veins of turquoise can be found running through the white rock.  There was some demand in the marketplace for this veined white material, so it is still found, marketed as "white buffalo turquoise" and sellers justify this name because it was "discovered" by "turquoise miners".  Again, this is just "creative marketing". 

As always, consumers need to protect themselves when purchasing turquoise, whether online or in person, by asking specific questions, getting a guarantee in writing, and learning as much about turquoise as possible.

Most of the information I used here in this post comes from a report written by Homer Millford, New Mexico Abandoned Mine Land Bureau.

A website that offers FANTASTIC information about genuine v. fake turquoise can be seen HERE.

Here is a "turquoise" pendant being sold on ebay for $300---it's not genuine at all, but is some sort of dyed howlite/magnesite (and certainly not worth that price):
THREE HUNDRED DOLLARS for that!  I love how they carefully hold it with tweezers. Some marketers believe that asking high prices for something means it's a "quality" item, and sadly buyers believe that.  Not true.  Please, buyer beware.

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