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| RaffaelloSanzio: Portrait of Maddalena Doni |
The name Ruby comes from the Latin Ruber,
which means “red”. Medieval Europeans wore ruby to succeed in Love, health and
wealth. Because of its color has always
been associated with passion, love and beauty. It is the world most famous and
best-loved red gem.
Is the most important colored stone in the market and is
the red variety of the gem species Corundum.
The quality of a ruby is determined by different factors, the most
important is the color. The finest Ruby
has a vivid red color with a light purple hint. In its purest form, the
corundum is colorless, but if some trace elements stick into the crystal’s
structure, the mineral can have some change in color. In the case of Ruby, the
trace element that affects the red color is the Chromium. The saturation of the
color depends of the quantity of Chromium present in the Corundum. Because the Chromium causes fluorescence, the
best ruby must have also some traces of Iron, which inhibits the fluorescence. 
Its hardness is 9 on the Mohs scale, is the hardest stone on Earth after
the Diamond.
Historically the best quality color ruby comes from the Burmese source,
which is described as “pigeon’s blood”.
Even though the origin of a Ruby is important to guarantee the quality,
not only Myanmar produces high quality gems, any ruby source can produce both
high and low quality stones.
The major sources of Ruby are in Asia: Myanmar, Thailand, Sri Lanka,
Cambodia, and Pakistan.
There are mines also in Africa: Madagascar, Kenya, Malawi and Tanzania.
Natural Rubies are very often included, and is also difficult find it in
big specimen. It’s rare see an eye clean ruby in exceptional size. The environment where the ruby forms makes it
difficult, for the crystal, to grow.
But the story is different for the sapphire, the brother of Ruby; the
blue stone is easily found in bigger size and less included.
Treatments are widely used to enhance the beauty of the Ruby, and the
heat treatment is now so common that is accepted in the trade, actually in
every gem market it is assumed that all rubies are heated, unless there is a
certificated that can prove it. Heat has multiple benefits; it works in both
color and clarity. Any brown shades, that lower the quality, disappear to bring
out the red color; while also the inclusions become less visible. Other used
treatments, less accepted from the trade, are dyeing and fracture filling.
Can happen sometimes, to see in the market the star ruby, the phenomena,
called asterism, is caused by the needle-like
inclusions into the stone, if is cut into a cabochon the light is reflected in
a 6-rays star. Those gems are highly priced and very rare.
Ruby and star ruby are both the US birthstones of July.
Ruby is one of the earliest colored stones to be imitated, with both
natural and synthetic materials. Glass
is the most common material used as imitator. Other material are: red spinel,
garnet, CZ, and dyed corundum.
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| Red Spinel |
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| Garnet |
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| CZ - Cubic Zirconia |
In late 19teen century, some scientist
introduced in the market a new kind of rubies manmade in lab. They found the
way to synthesize in the lab what Mother Nature makes in million years. The process
is quick and cheap. Those synthetic
rubies are now easily affordable, not expensive and look really good to the
untrained eye. But don’t worries, the gemologist has the knowledge to
distinguish between those and a natural one, if you want to buy a jewel with
Ruby, always ask for a certificated, just to be sure!
