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Testing To Destruction - China Blue Grass Turquoise

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Author Topic: Testing To Destruction - China Blue Grass Turquoise  (Read 2004 times)
Michael S Hoover - Redrummd
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« on: June 20, 2010, 09:04:32 pm »

I bought a cab of "Grass Turquoise" from China to test to destruction.  It was sold as "Turqouise" with a 6.0 MOHS hardness.

The first photo is the cab sitting on my graphite block.  It has a sprayed on finish that looked decent and I think actually harder than the supposed 6.0 MOHS hardness.  It could be carved with the 440C steel pocket knife I use and abuse on my workbench so it is not actually very sharp.  Note that there is a darker blue spot at the top of the cab which is the same color as the back of the cab which seems to indicate it was cut and then dyed as a slab with the top and back being a lot darker than the material in the middle.

Picture two shows the cab being partially burned.  it burned pretty well at first as the resin/polymer burned off and the third picture shows the cab smouldering for a while after removing the actual torch flame.

Picture four and five shows the actual material used to form the slab is mostly a powder and a lot of tiny fragments of the material that retain the blue dye color.  Based on its hardness it could be soft Turquoise or possibly Howlite, AKA "white turquoise".

The last picture shows the remaining largest piece after being polished.  It polishes very easily with ZAM so I again wonder why the sprayed finish other than consistency and ease for mass production.



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Taogem
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« Reply #1 on: June 21, 2010, 02:51:07 am »

That is just really ugly !

Never even heard of a Chinese Blue Grass before either..
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Enchantra
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« Reply #2 on: June 21, 2010, 06:28:42 am »

Ditto George, I've never heard of the stuff either.
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Michael S Hoover - Redrummd
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« Reply #3 on: June 21, 2010, 09:38:08 am »

Do an Ebay search for "grass turquoise" and you will find hundreds of listings.  If you do a search for "turquoise rough" and sort for most expensive first you will find listing for turquoise pieces up to 7 pounds from China that look pretty much like Howlite rough I have seen being sold at rock shows. 

So, basically I am always looking for large turquoise pieces for use on knives and I try to determine if the stuff being sold is really turquoise.  I am very suspicious that all of the China "Turquoise" is dyed Howlite at this point.

In fact I actualy found this in one of the Ebay listings for "grass Turquoise":

Item Description
This necklace is made from around 11 pieces of Grass Turquoise Howlite gemstones. The stones are round beads  in shape and are measured around 30mm. The stones are spaced by matching round beads and hand tied knots. Each stone is hand cut, crafted and polished into shaped.
 
 
  Material 100% Grass Turquoise Howlite 


It would be very hard to challenge any "Turquoise" listing as fradulent under Ebay rules as one of the common trade names for Howlite is in fact "White Turquoise".

The point of these tests is to be sure you understand that any low cost "turquoise" that does not have copper or pyrite in it, is very likely dyed Howlite in my opinion. 



 
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hulagrub
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« Reply #4 on: June 21, 2010, 10:25:02 am »

Michael, Just keep a burning and crushing and showing us your results. This too great!!  yippie
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« Reply #5 on: February 21, 2011, 07:12:58 pm »

Id love to cut through the resin and polish so we could get a refractive index reading on this stuff, Maybe a specific gravity test too. Ill bet this is anything but turquoise .
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Bryan
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« Reply #6 on: February 22, 2011, 05:57:54 am »

"White Turquoise".
now there is a selling point!
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David

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« Reply #7 on: February 22, 2011, 01:16:04 pm »

Its also being marketed as "White Buffalo Turquoise"
What a line of B.S. marketing!!!!
Bob
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« Reply #8 on: February 24, 2011, 06:06:01 pm »

Michael, thanks for the break down LOL.
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