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Red tiger eye


#1

Hello, I have recently received some red tiger eye. More recently I
have heard that all red tiger eye is heat treated. I was wondering,
is there any natural red tiger eye anywhere?

Thanks,
Adam Montoya


#2

Adam,

Tigereye’s natural color is blue. Mother nature heats it till it
turns honey…often you will find pieces that are blue with areas of
honey mixed in (sometimes called ‘hawkseye’. If she keeps heating
it, the honey will turn red. You can do it in your oven (not sure of
the temp though) if you wish. I have had in the past, pieces of
natural untreated tigereye with all three colors. Unfortunately I
did not keep any…its alll gone!! Some tigereye can also be
bleached to a grayish and even a greenish color.

Cheers from Don at The Charles Belle Studio in SOFL where simple
elegance IS fine jewelry! @coralnut2


#3

Hi Adam. Yes and no. And maybe. I’ve been told by people of some
experience that a lot of Tiger Eye/Tigereye/Tiger’s Eye (you pick
the nomenclature. GIA refers to it as Tiger’s Eye and I’ll stick
with that) is open-pit mined. Sometimes the brush is burned off,
occasionally turning the material red from the fiery blaze. In
effect, it becomes heat-treated via mining technique. Others say
that a brush fire won’t reach the temperature necessary to change
its’ color. Then again, much of it may have undergone a natural
heat-treatment in the earth’s crust by some long-past geological
event, possibly millennia before it was discovered and mined. Some
say that none of it comes out of the ground red and that all of it
must be treated to turn it red. I’ve never personally mined the
stuff, so I wouldn’t swear to anything other than it being
heat-treated by a human being. To add further to the confusion,
Tiger’s Eye is also commonly dyed or bleached, or a combination of
both. To make it even MORE confusing, the heat-treatment is
undetectable. In other words, anybody who practices proper
disclosure and did not actually mine the stone (and therefore see it
emerge from the ground as a natural red stone) must assume it to be
treated. Whoever told you that all red Tiger’s Eye is heat-treated
may have been practicing just such a disclosure. At any rate, the
heat-treatment has excellent stability and is unlikely to fade over
time. I know this sounds rather vague as opposed to a "yes or no"
answer, but sometimes, there are no “yes or no” answers in the
trade. Sincerely, James


#4

Dumorturite replaces asbestos/gypsum & creates a pink/fuchsia color
in some tigers eye from Arizona. I have some that I bought in
quartzite in 2002

Sincerely,
Nancy Stinnett, Owner
Geosoul Arts
http://www.geosoul.com
(702) 436-7685


#5

All, I have cooked tigereye to a very nice red color in my barbeque.
Beware tho, you can cook it too much and it will turn to a chalky red
that is very brittle. I have never been able to obtain the three
colors of red, blue, and gold by heat treating in one piece. All the
pieces I have treated became totally red. My estimate is that a
temperature of 450 -500 degrees fahrenheit is what is needed to
change the color.

Gerry Galarneau, in still hot Phoenix, Arizona. Cutting cabs from
Crinoid Marble, Script Jasper, Picasso Marble, etc…


#6

Yes,: It is called tiger iron and has hematite inclusion hence the
name and occurs in Australia’ there is also a metamorphosed tiger
eye called petersite and occurs in red blue and yellow… Ringman


#7
GIA refers to it as Tiger's Eye and I'll stick with that) is
open-pit mined. Sometimes the brush is burned off, occasionally
turning the material red from the fiery blaze. In effect, it
becomes heat-treated via mining technique. Others say that a brush
fire won't reach the temperature necessary to change its' color." 

Hi James, Unless I’m missing something here, isn’t what you’re
suggesting physically impossible? I mean, don’t the heat and flames
from fires in Africa act just like the heat from fires on the
American side of the globe… and rise? If they do, and if there’s
even the slightest bit of dirt beneath these burning bushes, how
could even the most intense flames ‘heat treat’ gem materials
that’re both beneath and insulated from them?

Curiouser and curiouser,

Douglas Turet Another Bright Idea! / Turet Design P.O. Box 162
Arlington, MA 02476 Tel. (617) 325-5328 eFax (928) 222-0815
anotherbrightidea@hotmail.com


#8
there is also a metamorphosed tiger eye called petersite and occurs
in red blue and yellow.... Ringman 

True Ringman, but…I believe petiersite is something different
though related. Tigereye actually derives from crocidolite, an
asbestiform or riebeckite. The crocidolite is replaced fy silica,
hence it is quartzified.

Petersite (possibly correctly spelled Pietersite but also seen as
Petiersite) is, I believe, related but has a different fiberous
construction. I have checked every one of the mineral books in my
library but cannot find a reference to Petiersite (or
petersite/pietersite).

On the other hand, I found a site known as Kashmere Blue" on line
with the following write-up: " Pietersite was first discovered by Sid
Pieters in 1962 while prospecting farm land. He registered the find
in the mineral records of Britain, which was published in 1964 naming
the material Pietersite.

Pietersite is formed from a crocidolite type asbestos or variety of
Riebeckite. The process begins with Hawk Eye, the name given to the
blue variety of Tiger Eye. This opaque aggregate is formed when
quartz replaces the blue/green mineral crocidolite creating
iridescent planes or fractures with a silky luster. Tiger Eye is
created when the iron from the decomposed crocidolite oxidizes
changing it to a golden brown color. Pietersite is then formed by a
process known as brecciation. This occurs when the fibrous structure
of both Tiger Eye and Hawk Eye are broken via the earth’s geologic
process. The tiny fragments are later naturally cemented together by
quartz creating a finished product with multiple hues and superb
chatoyancy. "

Cheers from Don at The Charles Belle Studio in SOFL where simple
elegance IS fine jewelry! @coralnut2