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Rubies quality

An approximate ranking of important rubybeen discovered. The first is about
origins is given below. This applies10-30 km. inland from the coastal town
only for the finest untreated qualitiesof Vatomandry, while the second is
from each source and is but a generalroughly 45-70 km. from the town of
approximation. In other words, aAndilamena. Vatomandry is said to
top-quality Thai/Cambodian ruby can beproduce the better-quality stone, being
worth far more than a poor Mogok stone.lighter and brighter (more reminiscent
Mogok, Burmaof Burma), while the Andilamena stone is
Sri Lankasomewhat darker and not as clean. Rutile
Madagascarsilk seen in some pieces suggests that
Nanyazeik, Burmastar stones may be forthcoming. Much of
Everything elsethe material from both deposits is
Mogokheat-treated.
When we talk ruby, we talk Burma. ForIt is still too early to properly rank
connoisseurs, no other will do. In theMadagascar in the ruby world, but the
days of yore, matters were simple. Burmastones I have seen so far suggest that
meant Mogok. This storied deposit wasthere is great promise.
known for over 1000 years as the home ofVietnam
the finest ruby on the planet.Beginning in the late-1980's, fine ruby
While Mogok is the traditional source ofbegan pouring out of two different
the world's finest rubies, good stonesdeposits in Vietnam. Although Vietnam's
are rare even from this fabled area.ruby originates from two different
Pigeon's blood was the term used tomining areas, Luc Yen (north of Hanoi)
describe the finest Mogok stones, butand Quy Chau (south of Hanoi), both
has little meaning today, as so fewsources display similar characteristics.
people have seen this bird's blood.There's nothing like time to put things
Mogok-type rubies possess not just redin perspective. In the late 1980's,
body color, but, by a freak of nature,Vietnamese ruby literally exploded on
red fluorescence, too. In addition, thethe world gem market. The best
best stones contain tiny amounts ofVietnamese ruby approaches fine Mogok,
light-scattering rutile silk. It is thisbut since the early 1990's most have
combination of features that gives thesetended towards pink. Today, little
rubies their incomparable crimson glow.facet-quality is produced, and even the
In Mogok rubies, the color often occurscabochon material rarely competes with
in rich patches and swirls, and colorthat available from MA?A׮g Hsu. Some
zoning can occasionally be a problem.pinkish star material is also produced.
The shape of Mogok ruby rough generallyKenya & Tanzania
yields well-proportioned stones.Stones from these sources are
In addition to faceted stones, the Mogokmagnificent when clean, but facet-grade
Stone Tract also produces the world'smaterial is rare. Like Burma, much of
finest star rubies.this material is strongly fluorescent.
Mang HsuStar stones are not produced from these
When the Mang Hsu deposit came on streamdeposits.
in 1992-93, it took the ruby world byOne specific deposit is worth
the storm. Suddenly, we were awash in amentioning. Beginning in the mid-1990's,
sea of red the likes of which had nevermines near Songea began to produce
been seen before. And fine stone it was,material with a dark, garnety color
too. This was not the garnet-like hue ofveering towards orange. While this
Thailand, but a rich, fluorescent red.material is ruby of a sort, it is
In 1992, the Mang Hsu (Maing Hsu)marginal due to its high Fe content.
deposit in Burma's Shan State beganAfghanistan
producing good material. This hasJagdalek has produced rubies that rank
continued to the present, so much sowith fine Mogok stones, but facetable
that close to 90% of the fine cab andmaterial is in short supply. Similar to
facet-grade ruby in the world market isVietnamese rubies, many of these stones
from this deposit. But most cut stonescontain small areas of blue color. They
are under two carats.are also strongly fluorescent, and if
Mang Hsu material can be extremely fine,the deposit ever produces clean
but virtually all is heat treated, andmaterial, watch out. No star stones
most is also flux-healed.here.
Nanyazeik (Nayazeik)Thailand/Cambodia
In the past year or so, rubies haveThis material's main attribute is its
started to come out of Nanyazeik inhigh clarity, but the flat crystal
Burma's Kachin State. I did see one fineshapes generally yield overly shallow
purplish red piece from this deposit onstones. Due to the high iron content,
my last trip to Burma in June, 2001.which quenches fluorescence, most stones
Only time will tell whether Nanyazeiktend to have a garnet-red color. An
has the makings of an important source.additional problem is the total lack of
Other than ruby, Nanyazeik has producedlight-scattering silk inclusions (star
some super red spinels, equal tostones are not found). Although heat
anything from Mogok.treatment does make improvements, it is
Sri Lanka (Ceylon)not enough. In Thai/Cambodian rubies,
The classic case of giving a dog a badonly those facets where light is totally
name. Some of the world's finest rubiesinternally reflected will be a rich red;
have come from Sri Lanka's gem gravels,the others appear blackish, as with red
but because of the erroneous "pinkgarnets. Thai stones are actually less
sapphire" moniker, they have beenpurple than most Burmese rubies.
largely overlooked. Top-grade Sri LankanHowever, Burma-type rubies appear red
reds are virtually indistinguishableall over the stone. Not only is a rich
from their Mogok brethren, but most tendred seen in the areas where total
towards purple or pink. As with Sriinternal reflection occurs, but due to
Lanka sapphires, color accumulates inthe red fluorescence and
large stones and so they can be quitelight-scattering silk, other facets are
magnificent in sizes of five carats oralso red.
more. Due to the bipyramidal shape ofWith the decline in Burma production
the rough, many stones are cut withduring the 1962-1990 period, the market
overly deep pavilions. Sri Lankan rubybecame conditioned to Thai/Cambodian
is strongly fluorescent and stars arerubies, with some people actually
common.tending to prefer them (in the land of
Madagascarthe blind, the one-eyed man is king).
When I was teaching gemology in Bangkok,Thai/Cambodian rubies are acceptable
I used to point to an island off theonly when good material from the
coast of Africa and inform my studentsBurma-type sources is not available.
that, if they wanted to hunt gems, thisToday, production from the Thai side of
would be a great place to start. Knownthe border is zero, and that from
in olden times as the "Beryl Island"Cambodia is negligible. One occasionally
Madagascar was long consideredhears statements about how Cambodian
mineralogical nirvana. And today, it isstones are superior to those from across
equally known for its gem wealth.the border in Thailand. This is untrue.
Prior to this year, Madagascar producedThe deposits are essentially one,
mainly fine blue sapphires and pinks.directly straddling the border.
But now two important ruby deposits have



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