There
is a ton of research and a ton of reading already out there with
respect to opals - their chemical composition, physical
structure and
more. Since this page is devoted specifically to shopping for
opal jewelry, we will stick primarily to the facts you need to know to
buy good quality opal jewelry.
There are six primary varieties
of opals used for jewelry manufacturing
purposes:
Boulder Opal
- A thin layer of opal naturally adhered to brown ironstone rock.
Andamooka Matrix
Opal
- Black or dark-bodied opal with bright specks of iridescent color.
Dark Opal
- Opal
that has a greyish or darkish appearance when viewed from the front.
Black Opal
- Opal that has a blackish appearance when viewed from the
front.
Black opals are rarer than light or dark opals and, therefore, more
expensive.
How
to Judge Opal
Color
One of the foremost qualities
to look at when buying opal jewelry is
the opal's 'play of color.' Is there a wide spectrum of color
present? Do the opal's colors have good depth and
fire?
Look at the opal jewelry from all angles. Is there good color
from all angles or are there dead zones? In general, the
intensity of an opal's color - its brightness and fire - and the
variety of colors present will determine the value and price of opal
jewelry.
For example, a 3 carat opal with intense fire and good
play of color with iridescent yellows pinks, greens and blues present
is rarer and generally pricier than a 3 carat opal with intense fire
and good play of color that exhibits only green and blue
iridescence.
It would be wise to remember at this point
that 'rarer' doesn't mean 'better' and it doesn't mean
'prettier.' The primary concern is that the opal jewelry you
purchase shows brightness and fire.
Solid
Natural Opals v. Opal Composites
Opal composites are
thin pieces
of natural opal glued to a black base
of a different material. This practice is quite
common and
makes for an affordable alternative to a solid natural opal and the
black backing oftentimes brings out the fire in an otherwise lukewarm
opal. The resultant composite has the general
appearance of
a black opal.
An opal doublet
is an opal composite that consists of thin slice of opal glued directly
on top of a black backing. An opal doublet will have a flat
top
surface.
An opal triplet
is an opal composite that consists of a thin slice of opal sandwiched
between a black backing and a crystal (clear) cap.
For the most part, genuine opals are used in opal doublets and triplets.
Opal
Hardness
Opals rate a 5.5-6.5 on the
Mohs scale of gemstone hardness,
making opals a rather delicate gemstone, probably best suited for
earrings, pendants and brooches. If, however, you opt for an
opal
ring - and there are some gorgeous ones out there - be sure you or the
recipient of the ring understand that special care should be taken to
avoid smacking that beautiful opal ring against hard surfaces where it
will surely come out on the losing end of things.
Opals are
sensitive to extreme and sudden temperature changes and, because of
their high water content (between 6-10% in gem-quality opals), will
crack and craze if allowed to dry out. That makes opal
jewelry
sound rather high strung, but unless you live in a very dry climate or
in very dry conditions, no special care is required when storing opal
jewelry. If you do happen to live in a dry climate, storing
your
opal jewelry in a air-tight container with a damp piece of cotton will
protect the opal from drying out.
Great care should be taken,
however, with the cleaning of your opal jewelry. A washing with a very
soft cloth, mild soap and room temperature water is best. Be
sure not to let opal doublets or triplets soak because the moisture can
erode the adhesion between the opal and its backing. And
harsh or
abrasive cleaners are out - your opal is a pretty soft gemstone and an
abrasive cleaning will scratch its surface and dull its
shine.
Ultrasonic cleaning machines are also out because the minute
vibrations can cause your opal to crack and can loosen the adhesive on
an opal doublet or triplet.
What
are Lab-Created
Opals?
Lab-created
opals/synthetic
opals are different than other lab-created
and synthetic gemstones. While lab-created diamonds,
sapphires
and rubies have the
same
chemical composition and physical properties as their natural
counterparts (they are, in fact, real gemstones - just not natural
gemstones), lab-created gem quality opals have
similar properties
as that of natural opals. Lab-created
opals tend to be brighter and have larger patches of color than natural
gemstones, with a more orderly pattern to their iridescence.
Lab-created opals do not have water content like natural opals do and
they are also much harder than natural opals, perhaps making a high
quality, lab-created opal ring a better choice than a natural opal ring.
As with natural opals,
lab-created opals should be scrutinized for
their depth, fire and play of color.
Opal
Jewelry Shopping Tips
- Look
for the opal's fire and play of color. View the opal jewelry
from
all angles to check for any 'dead zones' in its iridescence.
- Make
sure you know whether you're buying a solid opal, an opal doublet or an
opal triplet. Does the opal have a flat top
surface? If so,
then it's an opal doublet, a perfectly fine jewelry acquisition
provided that it's fully disclosed and appropriately priced.
Does
the opal have a clear top when viewed from the side? If so,
then
it's an opal triplet, again, a perfectly fine buy provided that it's
fully disclosed and appropriately priced.
- Be
sure you find out whether your opal is natural or
lab-created.
There are so many opinions out there as to whether a lab-created opal
replicates the beauty and appeal of a natural opal. A
connoisseur
of gemstone quality opals can probably tell within seconds whether an
opal is lab-created or natural. Stay away from lab-created
opals
that strike you as 'wrong ' - too orderly an appearance in its
iridescence, too bright, too garish in color. If a
lab-created
opal (heck, if any jewelry, lab-created or otherwise) leaves you
feeling lukewarm, you're not going to feel any better about it
years from now.
- If
you're shopping online, be sure to shop established, reputable online
jewelry dealers. Nearly all reputable online jewelry dealers
clearly state whether their gemstones are natural or
lab-created,
untreated or enhanced, a doublet or a triplet, etc. Be sure
to
read about the gemstone you're buying before
you buy
it so that you know exactly what you're paying for. Email the
dealer with any questions you have and check out return policies as
well. Most online jewelrydealers have a 30 day return policy
which makes it very easy to return your jewelry purchase if it isn't
what you expected.