In
March 2006, we have seen at AIGS
lab several attractive pink
to red rubies from 1 to 10 carats
presenting no indications of heat
treatment and some unusual internal
features compared to the usual rubies
we see at AIGS Lab mainly from Burma
or Madagascar. These rubies were
presenting features close to less
common rubies from Jagdalek (Afghanistan)
or Vietnam, but still some of their
inclusions were unusual for these
areas.
After some discussions with other
labs and our customers it seems
that all these rubies were obtained
from Tajik gem dealers coming from
Peshawar. The ruby owner was suspecting
these rubies to come from the Murgap
area in the east of Tajikistan near
the Chinese border.
On March 29th 2006, the Gubelin
Gem Lab issued a news flash
about these rubies:
**********************
Gubelin
Gem Lab News-Flash
**********************
Rubies from Tajikistan presented
as "Burmese rubies" on
the market. Over the past few weeks,
gem dealers presented several rubies
of good to very good quality in
the 5ct to 10ct range to the Gubelin
Gem Lab. The stones, which were
offered for sale in Bangkok and
Yangon, supposedly come from a "New
Burmese mine", and display
gemmological properties of marble-type
ruby deposits. However, advanced
microscopic, chemical and spectral
analyses show gemmological features
that do not match those of the known
Burmese deposits of Mogok, NamyaSek
and Mong Hsu. On the contrary,they
display properties consistent with
those described of rubies from the
Pamir mountain range in Tajikistan.
A research project of the Gubelin
Gem Lab on rubies and pink sapphires
from Tajikistan was undertaken in
1998, and the results thereof were
published the same year in the ‘Journal
of Gemmology’.
The gemstones presented to the laboratory
display a pinkish-red to red coloration,
often combined with a faint bluish
sheen, sometimes displayed in rubies
from other marble-type deposits
such as Vietnam and Afghanistan.
Fortunately, traditional and more
advanced analyses allow to distinguish
these Tajik rubies from those of
other known, commercially relevant
marble deposit.
************
(c) 2006 Gubelin
Gem Lab Ltd.
************
A study on these rubies was published
by Christopher P. Smith working
at this time for Gubelin in the
"Journal
of Gemmology.".
Some information about the area
and its rubies is also available
in "Ruby
and sapphire" by Richard W.
Hughes page 285 and 286.
The Murgap area was reported to
have produce rubies from marbles
in the late 1980s. Currently very
few is known about these area.
Another interesting ressource is
form Gary Bowersox website as he
visited the Murgap area in summer
2005: We can discover a Murgap
ruby in matrix from the
Dushanbe Gem museum. Then Bowersox
present some interesting photos
of the ruby mining area in his slide
show about the mining area.
A 200
carats Tajik ruby on
sale is Kabul is presented by Gary
Bowersox even if the stone is not
gem quality it show that large stones
are possible for the area.
Ken
Scaratt, Director of research
for GIA Research Thailand told us
that he has recently purchased in
Bangkok some cabochon grade rough
rubies from supposed Tajik origin.
After examination of these rough
stones, the author noticed that
the color of the cut stones and
the rough were very close. The internal
teatures of these stones also looks
very similar and match the information
provided by C.P. Smith in his 1998
article in the "Journal of
Gemmology".
The parcel
of 8 rough rubies provided
for comparison by Ken Scarratt,
Director of Research GIA,
Thailand. |
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Another
view of these rough cabochon
grade samples. Some white
matrix is clearly visible
on the rough samples giving
some indication about the
geologic origin of the stones. |
|
Details
on one of these rough ruby.
Some white matrix is still
attached to the stone.
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On March 01, 2006
during the Basel show (Switzerland)
I was able to see that some of these
Tajik rubies were proposed for sale.
Gubelin Gem Lab and SSEF gemologists
informed me that they have both
seen during the show some these
new stones including some attractives
stones over 5 carats.
As these stones are from marbles,
they can be mistaken for Burmese
gems but an experienced gemologist
familiar with Burmese rubies will
rapidly found out that the inclusions
in these stones does not match what
is currently know about Burmese
rubies. It was reported several
times that some of these stones
were currently presented in the
market as Burmese rubies or as Kashmir
rubies. "Kashmir ruby"
is an old term used by many Indian
dealers to describe rubies from
the west Himalaya from Kashmir,
to Afghanistan and Tajikistan.
I would like now to present you
a rapid inclusion study about these
unusual rubies in order to facilitate
their proper identification and
illustrate further more the information
available in the excellent study
by Christopher P. Smith in the "Journal
of Gemology" (1998). The
stones presented here were sold
as Tajik rubies in the Bangkok market
and were provided by
Scott Davies from American
Thai. in Bangkok, Thailand.
A parcel
of 14 of these unusual rubies
possibly
from murgap area in Tajikistan.
The color range from pink
to red, the size from 0.4
to 1.28 carats. |
|
Under
dark field illumination, we
can see clouds of exsolved
particles, feathers, and healed
fractures. The stone also
present some twinning planes. |
|
Details
on the exsolved particles. |
|
Details
from the exsolved particles
from another stone. |
|
General
view on a third stone were
healed fractures and exsolved
particles are the main inclusions. |
|
Details
on the particles. |
|
More
details at 80x |
|
General
view on another stone. Notice
the strong fluorescence and
the parallel "flakes" |
|
Details
on the particles and the "flakes" |
|
More
details on the "flakes"
that remind some inclusions
seen in some rubies from Vietnam. |
|
Other
view on the same inclusion. |
|
An other
stone presenting mainly particles
and liquids. |
|
Details
on secondary liquid inclusions.
|
|
Same
inclusions, under bright field
illumination. |
|
An interesting
network of liquid inclusions
arranged regularly in unusual
circular pattern. |
|
Details
on these liquid inclusions. |
|
Details
on a fingerprint. |
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Some
crystals are also present
as here. |
|
In several
stones white crystals are
arranged in clusters. |
|
Small
euhedral crystals. |
|
In the
same stones as the previous
photo, we can see negatives
crystals surrounded by fingreprints...
|
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Same
view under brightfiled. |
|
Same
inclusions using cross polars.
|
|
same... |
|
again...
|
|
General
view on a stone with liquid
inclusions |
|
Details |
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The stones
under immersion in Methylene
Iodine. |
|
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Details
on one stone. |
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Note:
The inclusion photos presented in
these pages can be used freely for
illustration and educational purposes
with proper credit to AIGS
Gemological Laboratory as I
took these photos while working
for the AIGS Laboratory in bangkok,
Thailand in March 2006.
Special
thanks for this issue to Scott Davies
from American-Thai
Trading, Richard
Hughes, Ken
Scarratt and Gubelin
Gem Laboratory for the help
provided.
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