Tuesday, August 30, 2016

Mojave Turquoise, Composite Turquoise---What Is It?

Genuine Turquoise
Turquoise has been a treasured gemstone across many cultures for thousands of years---Egyptians, Persians, Maya, Aztec, Native North Americans, Chinese---due to its beautiful blue-green color and metaphysical properties.  It is still a very popular gemstone, but is difficult to work with because it is very soft and brittle.  So several treatments are done on natural turquoise to make it wearable.
Natural Turquoise

Turquoise Treatments:
  • Natural and untreated turquoise is VERY rare (about 1% of all turquoise in jewelry)
  • Stabilized turquoise is treated in various ways, and is considered to be genuine turquoise.  Even Sleeping Beauty turquoise is treated.  Methods include heat, apoxy, and dyes.  Nearly ALL of the genuine turquoise sold is stabilized, including turquoise jewelry on shopping channels, in stores, and in jewelry retailers.
  • Reconstituted turquoise is considered to be NOT genuine turquoise.  It's powdered turquoise mixed with chemicals and glues and dyes.  It is unethical to refer to this as "genuine turquoise" as it is mostly other materials.
  • Block turquoise is made entirely out of dyed plastics and chemicals, and contains no turquoise.
  • Dyed Howlite/Magnesite is NOT turquoise, but is a simulated turquoise.
  • Yellow Turquoise is NOT Turquoise, but is African yellow jasper.  African green jasper is also sold as "green turquoise" but there is NO TURQUOISE in this stone---it is jasper, a type of Quartz.
So basically, you want to find "Stablized Turquoise" and not "Reconsituted Turquoise" for jewelry.  There is a new form of "mosaic" turquoise that is a stabilized turquoise, called "Mojave" or "Mohave" or "Copper Turquoise".

Blue Mojave Turquoise
There is a fairly new type of composite turquoise (since 2008) or "mosaic" turquoise that consists of pieces of genuine turquoise that are bonded together, along with other minerals (such as pyrite), using polymers.  Colors are added to the polymer to produce "Purple Turquoise" and "Green Turquoise", and "Red" or "Orange Turquoise".

The GIA (Gemological Institute of America) did a detailed exam of this turquoise in 2010 (you can read the pdf here) and it was found to be genuine turquoise.   Because small pieces of genuine turquoise are bonded into a larger piece, whether dyed or not, the end product is considered to be genuine turquoise.

The purple and green turquoise samples were dyed, and the blue composite turquoise was undyed.  The metallic "matrix" is found to be genuine ground pyrite or copper.  If you look closely, you can see the blue turquoise peeking through the colored polymers in both the green and purple examples below.  I assume they use yellow dyes to make the green, and reddish pink dyes to make the purple. 
Purple Mojave Turquoise

Green Mojave Turquoise

This is a BEAUTIFUL and affordable way to wear turquoise!  (These are genuine turquoise, so they aren't "cheap" but are well-priced.)   Although it's an assembled gemstone, it is made of all natural turquoise, and "blue Mojave turquoise" contains NO dyes.  The other colors are also extremely beautiful and interesting.  These are genuine turquoise gemstones, in a beautiful array of colors----much, MUCH more beautiful than dyed Howlite (which can be found in lots of weird neon greens and yellows, etc.) and made from all GENUINE turquoise pieces.

Turquoise, Spiny Oyster, MOP Composite Gemstones
I've seen some other beautiful assembled stones lately----turquoise and spiny oyster, "copper obsidian", some beautiful gems that look like they use pieces of mother-of-pearl plus black onyx, and more.  I am definitely going to buy some of these!  Here is one seller on Etsy, and there are many more, who have these beautiful new gemstones!  I'm not exactly sure what materials are used some of these assembled stones since they haven't been tested (the GIA's test was only for the Mojave Turquoise stones, and that was 6 years ago!) but there are new techniques in the jewelry industry every day.  If you search for "Mojave turquoise" (or spelled Mohave) or "Copper Turquoise", you will find a LOT of lovely choices!
"Copper Obsidian" Stones--plus Turquoise?

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