The big news in
gemstones beginning in 1993 is Burma Ruby. After an absence of almost
sixty years, the legendary crème de la crème of ruby
has reappeared in force. The Bangkok market is awash in Burma Ruby,
not just the odd single stone as in years past, but everything from
round calibrated melee sizes up to large single stones. This is
a supply situation that has not existed in the memory of most jewelers.
In fact, the Burma market has lain dormant for so long that most
jewelers, other than the very senior members of the jewelry industry,
have no familiarity at all with this almost mythic gem.
|Jean Baptist Tavernier. Beginning in
1631, Tavernier made a series of six voyages to India. During
his travels he saw some of the world’s most fabulous gems
ultimately purchasing (among others) the Koh-i-Nur and the Hope
diamonds for his patron Louis XIV of France.
For hundreds of years, through the first quarter
of the twentieth centuryBurma set the standard for fine ruby. Two
events set the stage for Burma's decline as the major ruby producer;
The first was the bankruptcy in 1934 of Burma Ruby Mines Ltd, a
British firm that held an official government monopoly. This reduced
ruby production to a trickle. The second event was the sealing off,
in 1962, of the Mogok mining district of Burma (now Myanmar) by
its communist government. This further reduced that trickle to an
erratic drip of stones across the Thai/Burma border. By the mid
1980's barely a handful of stones could be seen at any given time
in the gem entrepots of Bangkok.
Beginning in the nineteen sixties, most of the
world supply of ruby has come from the adjacent provinces of Chantaburi
and Trat in central Thailand near the Cambodian border and more
recently from a geologically similar area just across that border
as Thai deposits began to dwindle in the late l980's.
A recent series of events has dramatically changed
the political situation in Burma, leading to the increased availability
of Burma ruby. With the retirement of Burmese strongman General
Ne Win in 1989, a new, Communist regime has taken power.
The new government has adopted a more realistic
attitude toward gem mining. No longer are all stones expected to
be turned over to the government "for the good of the people."
Since March 1990 the new leadership has been actively promoting
joint ventures with private citizens. This partial privatization
has resulted in the re-opening of the famous Mogok stone tract,
a valley two miles wide and twenty miles long, the traditional source
of the Burmese gem. The infusion of capital brought in by these
joint ventures has led to the introduction of expensive mechanized
mining; bulldozers, backhoes and hydraulic techniques into areas
where formerly mining, officially banned, was carried out by hand,
clandestinely and mostly at night.
Photo: R. W.
Ruby rough, Mogok, Burma.
Mechanization has brought with it significant increases
in production. Although historically, mining at Mogok has been exclusively
alluvial (soft rock) deposits. The introduction of heavy equipment,
such as air hammers, has made the mining of in situ (hard rock)
deposits economically viable.
According to official statistics, which cover
only Government owned mines in the Mogok Stone Tract, ruby production
has burgeoned from approximately 10,500 carats (rough) in 1989-90
to about 39,000 carats in 1991-92. Of these seven mines, two work
exclusively hard rock deposits. In addition, there are at least
several dozen joint venture mines currently operating at Mogok.
Photo: J. Belmont
Everyone gets in the act in rubyland. The author looking
over tiny bits of ruby rough claimed from a local streambed
by local children. Mogok, Burma.
The current surge in production is also reflected
in increased supplies of Burmese blue Sapphire. This gem coveted
for its electric slightly violetish blue hue is considered by connoisseurs
to be superior to the Ceylon Sapphire, which currently rules the
market and is second in beauty only to the rare blues of Kashmir.
As of 1998, new mining areas such as Pyinlon in
the Shan State, Narawat and Namsha near the Chinese border and most
importantly, Mong Hsu in the Saihlian region of the southern Shan
State have come on line in the past few years. Mong Hsu, "officially"
discovered just last year is the major source of the calibrated
melee currently in good supply in the market.
Mong Hsu is in a part of Burma, near the Thai
border, which while nominally under the central government, is often
under the real control of The Shan State Army. This is a revolutionary
organization that has resisted the Burmese government since the
British pullout of Burma following the Second World War. Well-informed
sources that asked not to be named have suggested that a few powerful
Thai families are attempting to gain a monopoly on production from
Mong Hsu with an eye toward controlling prices and keeping an oversupply
of ruby from entering the market. However, at this writing, a free
market exists and goods are flowing steadily over the border into
|Drawings of some of the largest rubies
and topaz seen by Tavernier on his six voyages to India.
BURMA IS BETTER:
What makes the re-emergence of Burmese Ruby so
important is that clarity and cut being equal, the Burma stone is
far superior to the Thai ruby. Why is this so? In a word-- iron!
The Chantaburi-Trat mining district is iron rich. Thus, during the
ruby's formation somewhat over one hundred fifty million years ago
trace amounts of iron became part of the gem's chemical composition.
Iron lends the Thai ruby its characteristically brownish cast and
quenches the natural fluorescence of the ruby crystal. This means
that Thai Ruby is barely florescent under ultraviolet light.
By contrast, the pure white metamorphic marbles
of the ruby mining districts of Burma are iron poor. Conditions
in Burma are ideal for the formation of ruby crystals (Aluminum
Oxide with trace amounts of chromium) which are an exceptionally
pure red and which fluoresce strongly under ultraviolet light. As
any diamond lover knows, ultraviolet fluorescence, while technically
invisible to the naked eye, imparts an increased intensity to the
color of gem. This causes the color to radiate like the juxtaposed
hues of an OpArt painting or glow like a "blue-white"
diamond. Actually the Burma ruby will often fluoresce slightly in
visible light. The absence of the diluting effect of iron gives
the Burma ruby a superior color saturation.
|Natural Burma ruby crystal from Mogok
shown imbedded in metamorphic marble.
This does not mean that all consumers prefer Burma
to Thai Ruby. Many ruby lovers who have grown up with the Thai stone
prefer it to Burma ruby. In actual taste tests at the retail sales
counter, some customers show a clear preference for what they call
the darker color or tone of Thai ruby.
Ultraviolet fluorescence provides one of the keys
for separating Thai from Burma rubies. Establishing origin in ruby
is important because Burmese rubies have traditionally commanded
a price as much as twice that of Thai stones. It is a key, which
must be used with caution, however; because most man made stones,
including the newer Kashan and Ramaura synthetics, as well as natural
rubies from Vietnam, Kenya, Tanzania, and Afghanistan will also
fluoresce strongly under long and short-wave ultraviolet. Only inclusion
study coupled with florescence comparison can definitively establish
country- of- origin in ruby.
Ruby from the newer Vietnamese mines, as well
as some stones from Morogoro in Tanzania, compare favorably with
all but the very best of the Burmese. Both these areas are currently
active, measurably increasing world supplies.
When speaking about color in gemstones we use
the word "hue". Since no ruby is one hundred percent red
we speak of primary and secondary hues when describing this gemstone.
Pink, orange, blue, purple and violet are the normal secondary hues
found in ruby. The primary hue, must, of course, be red. In Burmese
Ruby the predominant secondary hue is pink. This is particularly
true in commercial grades.
The finer grades of ruby may exhibit any of the
above secondary hues. Experts disagree as to which of the secondary
colors is preferable. Some prefer a true red-red, others believe
a bit of orange frames and intensifies the red; yet others like
a slight pinkish cast. Therefore nebulous terms such as pigeon blood
are best avoided. A ruby, which is approximately 85% red primary
and no more than 15% of any of the above secondary hues, should
be judged as fine color. Stones with over 20% of any secondary color
begin to enter the commercial range.