cobalite/cobaltite???
James W. Anable, Jr.
I am hoping that you will be able to help me identify and price a stone
that I just purchased.
I recently bought a stone that is represented by the previous owner to
be an extremely rare piece of Cobalite. It was supposedly found during
a deep earth core sample searching for oil. The rough stone was
supposedly cut by the seller's brother (Steve Churchman?). The seller
told me that she believes it to be extremely rare, and possibly one of
the nicest pieces in existence.
The stone is an intense, almost fluorescent, cobalt blue color in
natural or fluorescent lighting. Under incandescent lighting, there is
a dramatic color change to purple with red flashes.
It has a nice Portuguese cut, with one very small chip on the back
point. It is 16.94 mm in diameter and quite deep. It weighs 18.13
carats. Without magnification, you can see little specks in it and a
couple of minor white flakes.
The first gemologist to look at it was somebody that I had asked to find
stones for me. His initial impression was that it looked synthetic.
Under the scope, he could see a lot of gas bubbles and the crystalline
white impurities. He could come to no conclusion, but could not rule
out that it was a fake. If it wasn't for the white inclusions, he would
have sworn that it was man made glass.
Northwest Gemological Laboratories in Bellevue, WA. concluded that it is
some kind of glass. Another highly respected gemologist in Seattle
(Alan J. Chappron) said that it looks like some "funky kind of plastic,"
because it felt warm to the touch and began to flow at a lower
temperature than man-made glass! Everyone else said that it was NOT
plastic, but maybe glass.
A jeweler in SeattIe had actually seen this material more than 10 years
ago. He remembered the name of the stone cutter (Wallace Wood, Wood
Lapidary, Seattle) and put me in touch with him. I showed him my
stone. He said that said he had also purchased some of this "cobalite"
with the same story that it was found during a deep core sample looking
for oil in Texas, about fifteen years ago. He said that my piece is not
his cut, but the material looks the same (blue to purple color change in
incandescent, with spherical gas bubbles and white crystalline
inclusions). He claims that he sent one of his samples to the GIA at
the time, and that it came back "glass-like substance of unknown
origin." He also said that the material has been on the market in L.A.
from time to time. He said that he thinks that it retailed for $120 to
$500 per carat. My stone is large with nice cut, but too many gas
bubbles to be considered $500 material. Even so, it is a very
impressive stone.
A second gem cutter said that the RI could be either glass or plastic,
but that the one very small chip on the stone was not conchoidal, as he
would expect for glass or plastic.
Eugene Cisneros of Mineralogical Research Co. told me that he has seen
this material and that a man by the name of Will Fretch (sp?), formally
of Fresno, CA (now deceased) had owned some of this.
I think that the name of the man that supposedly cut this stone from the
rough is Steve Churchman. If that name rings a bell, please contact me.
The following site shows a tumbled stone of lesser quality, but similar
color in parts:
http://nen.sedona.net/ancientvoices/hall1.html
Jewelers generally comment that it looks fake, too good to be natural.
It is really a stunning stone! I need to make a decision SOON!!! I
would hate to return it and regret it later. I would also hate to pay
$31/carat for glass!
If you can be of any help in any way, please contact me ASAP. Please
feel free to pass this message on to anyone who might be able to help.
Thanks,
Jim Anable
Seattle, WA
ana...@halcyon.com
ph: (206) 329-5918
1 Lucky Texan
Howdy Jim,
I refuse to GUESS as to the actual origin or composition of this
material. I am just replyig to suggest that,based on your statements,you
should NOT pay $31 a carat for it. If you like this stone,I believe you
could do better by buying color change synthetic corundum. Higher R.I.
and more scratch resistant than 'glass' or 'plastic' or Laser Gem.
Good Luck!
Carl
1 Lucky Texan
Mr. John E. Bittman
There is a mineral called Cobaltite, a primary source of cobalt. The
color is steely to silvery, with a touch of red. It is not blue.
Cobaltite is very heavy, with a specific gravity of over 6. Based on
the data you presented, my guess is you are being offered some pretty
glass.
Jack Bittman
Part-time golfer, gofer, gemologist, and goof-off--
but happy in retirement.
Naomi Pearson
Hi Jim just another comment to add to the confusion! A year or two
back the American Lapidary Journal had a single page article about
"cobalite" (as distinct from the ore mineral cobaltite which is quite
different), and it was claimed to be a natural and intensely colored
glass retrieved from an oil well(?) I think, just as indicated by
another poster. I have examined several examples of this under the
microscope myself and also am convinced that it is a glass, but
whether it is a natural and rare/expensive material (as suggested by
Lap Jnl) or a manmade dupe I can't say. It's very p[retty color
though! ........................Grtant Pearson
Jon Rolfe
>> I recently bought a stone that is represented by the previous owner
to
>> be an extremely rare piece of Cobalite. It was supposedly found
during
>> a deep earth core sample searching for oil. He said that he thinks
that it retailed for $120 to
>> $500 per carat. My stone is large with nice cut, but too many gas
>> bubbles to be considered $500 material. Even so, it is a very
>> impressive stone.
>> It is really a stunning stone! I need to make a decision SOON!!! I
>> would hate to return it and regret it later. I would also hate to
pay
>> $31/carat for glass!
>>
> I refuse to GUESS as to the actual origin or composition of
this
>material. I am just replyig to suggest that,based on your
statements,you
>should NOT pay $31 a carat for it. If you like this stone,I believe you
>could do better by buying color change synthetic corundum.
I have had a lot of trouble with this thread, and figured if I shut up
for a week or two, I wouldn't oner react.
For one thing, either on the Rockhounds mailing list, or on the
faceter's digest, I thought this material was pretty well dismissed by
someone with pretty heavy credentials.
Also, I have a problem with someone feeling pressured to make a decision
"soon", after hearing a story like the deep core find. I believe it was
mentioned that the geology in that area is not consistent with that type
of material.
My reaction (Just mine) to being offered an unheard-of material at a
high price would be to call the Police. We have, over the years, seen
some interesting marketing in this business, with made-up exotic names
having no basis in minerology.
URL: http://www.argo.net/~jnlrlf
Gemstone Fun:
http://www.argo.net/~jnlrlf/gempage.htm
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address.
(Sorry, but have had it with the "Opportunity to Get That
Porsche" mailings!)