Rubies quality

An approximate ranking of important ruby originsnirvana. And today, it is equally known for its gem
is given below. This applies only for the finestwealth.
untreated qualities from each source and is but aPrior to this year, Madagascar produced mainly
general approximation. In other words, afine blue sapphires and pinks. But now two
top-quality Thai/Cambodian ruby can be worth farimportant ruby deposits have been discovered.
more than a poor Mogok stone.The first is about 10-30 km. inland from the
Mogok, Burmacoastal town of Vatomandry, while the second is
Sri Lankaroughly 45-70 km. from the town of Andilamena.
MadagascarVatomandry is said to produce the better-quality
Nanyazeik, Burmastone, being lighter and brighter (more reminiscent
Everything elseof Burma), while the Andilamena stone is
Mogoksomewhat darker and not as clean. Rutile silk seen
When we talk ruby, we talk Burma. Forin some pieces suggests that star stones may be
connoisseurs, no other will do. In the days offorthcoming. Much of the material from both
yore, matters were simple. Burma meant Mogok.deposits is heat-treated.
This storied deposit was known for over 1000It is still too early to properly rank Madagascar in
years as the home of the finest ruby on thethe ruby world, but the stones I have seen so far
planet.suggest that there is great promise.
While Mogok is the traditional source of theVietnam
world's finest rubies, good stones are rare evenBeginning in the late-1980's, fine ruby began
from this fabled area. Pigeon's blood was the termpouring out of two different deposits in Vietnam.
used to describe the finest Mogok stones, but hasAlthough Vietnam's ruby originates from two
little meaning today, as so few people have seendifferent mining areas, Luc Yen (north of Hanoi)
this bird's blood.and Quy Chau (south of Hanoi), both sources
Mogok-type rubies possess not just red bodydisplay similar characteristics.
color, but, by a freak of nature, red fluorescence,There's nothing like time to put things in
too. In addition, the best stones contain tinyperspective. In the late 1980's, Vietnamese ruby
amounts of light-scattering rutile silk. It is thisliterally exploded on the world gem market. The
combination of features that gives these rubiesbest Vietnamese ruby approaches fine Mogok,
their incomparable crimson glow. In Mogok rubies,but since the early 1990's most have tended
the color often occurs in rich patches and swirls,towards pink. Today, little facet-quality is
and color zoning can occasionally be a problem.produced, and even the cabochon material rarely
The shape of Mogok ruby rough generally yieldscompetes with that available from MA?A×®g
well-proportioned stones.Hsu. Some pinkish star material is also produced.
In addition to faceted stones, the Mogok StoneKenya & Tanzania
Tract also produces the world's finest star rubies.Stones from these sources are magnificent when
Mang Hsuclean, but facet-grade material is rare. Like Burma,
When the Mang Hsu deposit came on stream inmuch of this material is strongly fluorescent. Star
1992-93, it took the ruby world by the storm.stones are not produced from these deposits.
Suddenly, we were awash in a sea of red theOne specific deposit is worth mentioning. Beginning
likes of which had never been seen before. Andin the mid-1990's, mines near Songea began to
fine stone it was, too. This was not theproduce material with a dark, garnety color
garnet-like hue of Thailand, but a rich, fluorescentveering towards orange. While this material is ruby
red.of a sort, it is marginal due to its high Fe content.
In 1992, the Mang Hsu (Maing Hsu) deposit inAfghanistan
Burma's Shan State began producing goodJagdalek has produced rubies that rank with fine
material. This has continued to the present, soMogok stones, but facetable material is in short
much so that close to 90% of the fine cab andsupply. Similar to Vietnamese rubies, many of
facet-grade ruby in the world market is from thisthese stones contain small areas of blue color.
deposit. But most cut stones are under twoThey are also strongly fluorescent, and if the
carats.deposit ever produces clean material, watch out.
Mang Hsu material can be extremely fine, butNo star stones here.
virtually all is heat treated, and most is alsoThailand/Cambodia
flux-healed.This material's main attribute is its high clarity, but
Nanyazeik (Nayazeik)the flat crystal shapes generally yield overly
In the past year or so, rubies have started toshallow stones. Due to the high iron content, which
come out of Nanyazeik in Burma's Kachin State. Iquenches fluorescence, most stones tend to have
did see one fine purplish red piece from thisa garnet-red color. An additional problem is the
deposit on my last trip to Burma in June, 2001.total lack of light-scattering silk inclusions (star
Only time will tell whether Nanyazeik has thestones are not found). Although heat treatment
makings of an important source. Other than ruby,does make improvements, it is not enough. In
Nanyazeik has produced some super red spinels,Thai/Cambodian rubies, only those facets where
equal to anything from Mogok.light is totally internally reflected will be a rich red;
Sri Lanka (Ceylon)the others appear blackish, as with red garnets.
The classic case of giving a dog a bad name.Thai stones are actually less purple than most
Some of the world's finest rubies have comeBurmese rubies. However, Burma-type rubies
from Sri Lanka's gem gravels, but because of theappear red all over the stone. Not only is a rich
erroneous "pink sapphire" moniker, they havered seen in the areas where total internal
been largely overlooked. Top-grade Sri Lankanreflection occurs, but due to the red fluorescence
reds are virtually indistinguishable from their Mogokand light-scattering silk, other facets are also red.
brethren, but most tend towards purple or pink.With the decline in Burma production during the
As with Sri Lanka sapphires, color accumulates in1962-1990 period, the market became conditioned
large stones and so they can be quite magnificentto Thai/Cambodian rubies, with some people
in sizes of five carats or more. Due to theactually tending to prefer them (in the land of the
bipyramidal shape of the rough, many stones areblind, the one-eyed man is king). Thai/Cambodian
cut with overly deep pavilions. Sri Lankan ruby isrubies are acceptable only when good material
strongly fluorescent and stars are common.from the Burma-type sources is not available.
MadagascarToday, production from the Thai side of the
When I was teaching gemology in Bangkok, Iborder is zero, and that from Cambodia is
used to point to an island off the coast of Africanegligible. One occasionally hears statements about
and inform my students that, if they wanted tohow Cambodian stones are superior to those
hunt gems, this would be a great place to start.from across the border in Thailand. This is untrue.
Known in olden times as the "Beryl Island"The deposits are essentially one, directly straddling
Madagascar was long considered mineralogicalthe border.