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Blue-black tiger eye

When I was a youngster I cut and polished thousands of agate cabs for
my father. He purchased some tiger eye from south africa that was a
beautiful blueish -black with gold streaks running through it. I made
a ring with this material and had it stolen. This stuff is much more
interesting than normal tiger eye but I have never seen it in a
retail ring. Does anyone out there Know of a
source for this material, preferably finished?


New Era Gems at has "Tigereye (Golden Blue
and Variegated). it isn’t finished, but the rough is very pretty. this
is the only source i know other than a rock shop here in estes that
may have some in the 25 cent pebble box. :wink:

susannah and shawn

If I remember correctly from my tiger eye cutting days in the 80’s,
blue tiger eye is a heat treated form of golden tiger-eye. It seems
conceivable that if the process was stopped mid-stream, the result
would be a semi-blue. It also seems conceivable that finished stones
could be heat treated. I don’t have any resources on gemstone
treating, so I can’t confirm this or lend further guidance. With a
little research you might be able to develop your own solution using
an appropriate piece of golden tiger eye.

Hope this helps!


Dave Sebaste
Sebaste Studio and
Carolina Artisans’ Gallery
Charlotte, NC (USA)

Your lucky day! I have blue black tiger-eye with gold streaks… Also
I can cut to order… Ringman john

Sounds like some Pietersite I have. I don’t have a source for cabs but
Hannes Kleynhans at mines the material - US$50
per kilo last time I asked.

Andy Parker, Agate House Lapidary
Ulverston, Cumbria, England
Tel: 01229 584023

Oops, sorry for that incomplete post I just sent off! It seems to me
like the blue tiger’s eye is called hawk’s eye. Isn’t it the red
stuff that has been heat treated?? Rose Alene McArthur

the material you had was partially altered crocidolite,ususually sold
un der the trade name"hawks eye".since it is the mineral that quartz
takes t he form of to become tigereye it is found at same sources.try
house of on yx in greenville,ky.

I’ve gotten some blue/gold tiger-eye from Ron Everett of Ron’s Rocks
up in the Los Angelos area. Don’t know if he has any right now. The
material was good quality, about 6-8 bucks a pound. You can contact
him at If he doesn’t have any finished cabs in the
blue/gold material, let me know and I can cut a couple for you and
trade you for something.

Dan said: “… He purchased some tiger eye from south
africa that was a beautiful blueish -black with gold streaks running
through it”

If you ask for hawk’s eye, that might help you in finding a cab of
it. The blue is the color of the original crocidolite, which is
replaced by quartz. The hawk’s eye can alter through oxidation to the
tawny golden tiger’s eye, and sometimes this alteration is
incomplete, leaving some blue areas intact.

There’s an image of some rough at the bottom of the page below
showing blue and gold in the same piece. You can click on the image
for a larger view more clearly showing the gold among blue areas on
the bottom right: HTH, Carol
Carol J. Bova @Carol_J_Bova

Blue -black tigereye is I believe called ‘Falcons-eye’ while the
yellow variety has the name tigereye.

As this material, crocidolite is blue asbestos with a silica
infilling I would suspect that the falcons-eye has not been subjected
to the same geological heat and or pressure of the yellow variety.
The yellow will go red if heated and in fact there is a variety found
in West Australia which they call ‘tiger-iron’ as it has bands of
haematite running through it while the bulk of the stone can be a
mixture of reds and yellows.

However, if you get really stuck for a piece of falcons-eye I have 2
small pieces which remain from a large piece I trimmed prior to flat
lapping. They are small but large enough to cut 10x8 or maybe 12x10.

Happy to send them on as I have no use for them.

Keith Torckler, Cornwallis, New Zealand

 If I remember correctly from my tiger eye cutting days in the
80's, blue tiger eye is a heat treated form of golden tiger-eye. 

While it is possible to color-enhance golden tiger’s-eye by various
means, it is also true that blue tiger’s-eye, also known as
hawk’s-eye, exists in nature. It comes primarily from South Africa
and is related mineralogically to but is different in appearance from
Pietersite, in that the fibers causing the chatoyancy are parallel to
each other rather than randomly patterned, thus producing the "eye"
effect. All of these minerals are part of the quartz family.

While I don’t know where to buy finished hawk’s-eye stones, I do have
a rough slab of beautiful material that I bought from a dealer about a
year ago. I don’t know if he still has any left but, if you’re
interested in rough, email me off-list and I’ll find out.


HI Rose, Yes, tiger’s eye can be heated to get the red form, called
ox’s eye, or bull’s eye (I guess because it’s oxblood color?). Carol

Carol J. Bova @Carol_J_Bova

Attn. Beth; Heating tiger eye will turn the stone RED… The blue
enhancement,I’ve been told is from a form of die… For the recore,I
gave up years ago at trying to cab this material… Enjoy–


Hi, at a San Francisco gem and mineral show I purchased some beautiful
Pietersite, which I was told is a close relative of Tiger eye , and
also comes from South Africa. It has the typical shiny-fibrous
appearance, but comes in dark-blue with black, auburn and yellow
swirls. The appearnce is svery similar to tigereye altough I would
not bet on the chemical identity. Any experts orchidians out there to

I believe Pietersite is a brecciated tiger’s eye- i.e, tigers eye,
hawks eye, etc that has been fragmented by geologic processes and
solidified through pressure and deposition of additional silica.

Lee Einer

There seems to be some confusion between Pietersite, crocidolite,
tigerseye, blue-black tigereye, falconseye and hawkseye.

The following is an extract describing Pietersite which would
indicate it is not a brecciated crocidolite as its only affinity with
that mineral is silica (jasper) and asbestos but has been formed in a
quite different manner.

Pietersite crystallises in the form of masses, the structure a result
of inclusions in jasper where the inclusions are pseudomorphs after
asbestos. The colour is blue/black and the mineral exhibits a
chatoyant quality. It was discovered by Sid Pieters, Windhoek,
Namibia, and is truly lovely.

Re the blue-black tigereye (crocidolite) it is apparent that this is
generally named ‘hawkeye’ in the USA, however in Minerals Rocks and
Gemstones by Borner he describes it as ‘Falconseye’ so I guess it
only a very short step from falcon to hawk.

I have included this excerpt re crocidolite:

This quartz composite stone begins as a fibrous blue mineral called
crocidolite, which is comprised of iron & sodium. In some resources
crocidolite is referred to as asbestos. The transformation begins as
clear Quartz becomes imbedded between the fibers of crocidolite. The
completed process will result in one of two a blue stone
called Hawk�s Eye or the golden brown stone called Tiger�s Eye. As the
gem forms the iron & sodium are completely dissolved, the quartz
takes on the fibrous formations & the blue color of crocidolite. This
creates the parallel lines within the gem giving it the liquid luster
& light movement the stone is so loved for. Even though the iron &
sodium dissolve, traces of hydrated oxide of iron deposit between the
crocidolite & Quartz, creating the yellows that are common to both
Hawk�s Eye & Tiger Eye. How much of this hydrated mineral is
deposited will determine how red, yellow or brown a Tiger Eye will
be. The rarer blue Hawk�s Eye will have only the slightest amounts.

Hope this helps to sort things out.

Keith Torckler, Cornwallis, New Zealand