|
Back to Gemstones
OPAL
In Twelfth
Night Shakespeare referred to opal as "the queen of gems' "
The Roman historian Pliny described it as having "the fire
of the carbuncle, the brilliant purple of the amethyst and the sea
green colour of the emerald, all shining together in incredible union
' "
The Romans considered
opal a symbol of hope, an appropriate attribute for a gem with a
rainbow locked within it. The Arabs believed opals fell from heaven
in flashes of lightning, thus acquiring their fiery colours.
These romantic
notions are inspired by one of the most uniquely beautiful gemstones
nature has ever produced-the dramatic, mysterious opal. The phenomenon
displayed by opal is called play of colour. It is caused by the diffraction
of light set up by the layers of silica spheres in its composition.
The effect is similar to the rainbow colours displayed on a soap
bubble, only much more dramatic.
In the 19th
century opal acquired a stigma through its role in the plot of a
novel by Sir Walter Scott, Anne of Geierstein. The heroine owned
an opal that burned fiery red when she was angry and turned ashen gray
upon her death. Queen Victoria finally dispelled the curse
by giving opal jewellery wedding presents to her relatives.
Opal has long
been regarded as an October birthstone, sharing the spotlight with
tourmaline. The famous French actress Sarah Bernhardt was born in
October and never considered herself well-dressed unless she was
wearing opals.
IMPORTANT
VARIETIES
The most treasured
variety of opal is black opal with strong play of colour, that is,
brilliant flashes of different colours. Black opal is so called because
of its dark background colour.
The variety
known as white opal has a light background, and the colours displayed
lean toward the pastel hues.
Crystal opal
has a colourless background and exhibits play of colour, but, unlike
white or black opal, it lets light pass through it.
Fire opal is
also fairly transparent, but its background colour may be yellow,
orange, red or brown. Sometimes it doesn't even have the typical
play of colour. It's often called Mexican opal because Mexico is
a major source of this type. Fire opal with a red body colour is
also known as cherry-v opal.
Opal that is
colourless, transparent to semitransparent and has little or no play
of colour is called jelly or water opal.
Opal quality
is judged by the number of colours exhibited and the evenness of
the pattern.

AUSTRALIA'S
GIFT
Australia is
the world's most important source of opal. The opal miner is a strange
breed of individual. He chooses to lead a spartan life in a particularly
barren and dry-y corner of the world while he searches for his rainbows.
To escape the extreme temperatures, he must burrow a home underground.
Opals are usually
found in sandstone or claystone. Deposits are spread over a wide
area, and there is little clue to their location. Mining is done
on a small scale with hand-operated machinery and small tools. A
pocket knife might be the final instrument to loosen an opal from
its host rock.
MAN
MIMICKING NATURE
Over the past
century scientists have become highly skilled at creating laboratory
facsimiles of fine gemstones. Far from being mere look-alikes, these
synthetic gems are made of exactly the same material that nature
uses and mimic the natural structure perfectly.
Synthetic opal
first came on the market in 1974 and has been improving ever since.
A skilled gemologist like a member of the American Gem Society can
distinguish it from natural opal by viewing it under magnification,
but to the untrained eye it looks natural.
THE
VERSATILE OPAL
Because opal
displays a whole rainbow of colours, it can be worn with any colour
outfit. It is usually cut in a dome shape and set in rings, earrings,
pendants, bracelets and pins. It may be joined by accents of ruby,
sapphire or emerald to enhance particular colour flashes in the gemstone.
A fine opal piece is often guarded in a web of small diamonds as
are other exceptional coloured gems. Some opals are fashioned into
beads for a major contribution to a woman's total look.
MAKING
A WISE PURCHASE
Since subtle
differences in quality can make large differences in beauty (and
price), it is important to select your jewellery from a professional
who can guide you honestly and ethically in your purchase.
Our firm is
a member of the American Gem Society. As a condition of membership,
we are re-examined each year to meet the Society's high standards
for knowledge, professionalism and integrity. The AGS symbol is
the hallmark of consumer protection within the jewellery profession
- as it has been for over 50 years.
Many gems are
processed to enhance their natural beauty. Ask your American Gem
Society Jeweller to discuss which techniques might apply to the
gem of your choice.
|