I am quite surprised that nobody has mentioned rear setting of
Opals.
Using this method a very robust and protective bezel can be built
and there is little chance of damaging the opal as the rear setting
is just a matter of a couple of prongs or a retaining ring.
Another advantage is if the stone is accidentally hit there is a
very high possibility that it will push out of setting instead of
shattering.
Tony.
Anthony Lloyd-Rees.
www.OpalsInTheBag.com
Hello everyone,
This discussion raises a thought. Donald noted the use of a thin film
of two-part epoxy to level up a floor for an opal before setting. I
recall a past comment that advocated placing a bit of glue,
specifically at points of the stone, before setting. The purpose
being to protect that fragile part during setting. The glue had
nothing to do with securing the stone in the setting. Seems like a
good idea to cushion the stone.
What say you all??
Judy in Kansas, where the half inch of rain last night was wonderful
and came at just the right time for my newly planted mums.
Years ago I used to cut a lot of opal and at the time I was
instructed not to bezel opal because of the possibility of expansion
and contraction of the stone with temperature and the bezel not
giving the same way and causing the opal to crack. Has anyone
experienced this or is it really not a problem?
Thanks, FredM
I am providing a service to my customer, and in the end it is their needs and limitations that determine my path forward on their jewelry, and not my own ego or wishes.
When I started in this business, I was told that 10 years I would
have to work just to establish my reputation and then my reputation
will work for me for as long as I maintain it. And it turned out to
be about right. What you call ego, I call protecting my investment.
But I do not want to create an impression that I somehow apologetic
for my ego. Far from it. One cannot practice goldsmithing without
one.
Leonid Surpin
The purpose being to protect that fragile part during setting. The glue had nothing to do with securing the stone in the setting. Seems like a good idea to cushion the stone.
Definition of gemstone is RARITY, BEAUTY, and DURABILITY. All three
must be present to call something a gemstone. If gemstone cannot be
set by normal methods, it means that durability is lacking and it is
not a gemstone. There are many technical reasons why it should never
be done. But the ethics alone should be enough of deterrent. By
setting stone with glue, one perpetrates a fraud on a client.
Leonid Surpin
I found out that Opals do dry out if left in the unset storage
containers.
Many owners never touch these stones for weeks or months. Then they
will get little hairline cracks in them. Once the setter gets to set
themā¦ācrackā and he is to blame, but it wasnāt his fault to start
with.
One company had a policy to always smear these soft stones with
āMineral Oilā. This prevented any form of cracking even while left in
the drawers.
In the Winter (dry air) is the worst time to store these stones.
Always go and examine how your stones are looking and then oil them
every other week or so. If not, its your money down the drain for
you!!!
ā¦Gerry!
Iāve never had a problem with itā¦but all bezel sets are made with
22K gold and might be able to expand or contract enough to offset
whatever the stone is doing
I've never had a problem with it....but all bezel sets are made with 22K gold and might be able to expand or contract enough to offset whatever the stone is doing
In 40 years I have never heard this one before. I love creativity
except when it conflicts with reality. I heard you can take an opal
to a plastic surgeon and get them filled with silicone to make them
bigger.
Richard Hart G.G.
Denver, Co.
But I do not want to create an impression that I somehow apologetic for my ego. Far from it. One cannot practice goldsmithing without one.
Definitely no false assumptions there 
Although you donāt need an ego imo 
CIA
Hello all,
Definition of gemstone is RARITY, BEAUTY, and DURABILITY
If diamond -being plane pressurized carbon- mines need to be closed
or blowed up in the sky to controle the price, their not rare
anymore. If the argyle mine produced more then 9 miljon carats a year
(for 2011) of diamonds, where is the rarity then?
That as a single mine amongst more then 30 knowing mines on earth
and itās not even the biggest one.
The biggest mine (most production) found up to 25 miljon carats in
2011. World For the ones who believe that industrial diamonds are
included, theyāre not. The total amount of diamonds is 144.000.000
carat a year (for 2011)! Diamonds are forever but rareā¦ no way.
The definition of what a gemstone is should be reviewed instead of
using rarity, beauty and durability.
I understand the consept of this ārarityā subject. However, to my
opinion, all of this is more related to money and marketing then to
rarity. In the same context, softer stones (lower then 7 or even 5 on
Mohs scale) are gemstones aswell and do not answer to durabilty.
I know that fellow jewellers will have a different opinion and some
of them will not like the facts but thatās the way it is.
Have fun and enjoy
Pedro
Excepting pearls on posts Iād never think of using glue to set a
stone. Now, Iām not a setter, but if a setter suggested gluing in a
stone Iād never use him again. However, there was an instance years
ago where I had to use epoxy, not to set a stone but to take out the
last bit of wobble.
When I first started in the trade I worked for Hans Engelhart (S.
Engelhart & Co., 18 E. 48 St.). This was back in the early 80s,
Leonid might remember them. Most of our pieces went to T&Co., thisād
be back when Willy Kalish was the shop foreman at Tiffany.
Anyway, in the shop were Mr. Engelhartās uncles, two brothers then
in their late 70s, who were exemplary setters. They used to get
pieces to set from jewelers up and down the East coast. I never
actually knew their names, they were just āthe uncles.ā
One day a ring came in from Tiffany for repair. It was an Egyptian
revival ring from the 20s, platinum, set with a single, large,
pyramidal cabochon sapphire. The sapphire was about 15 carats, a true
Kashmir blue and remarkably clean; a real gem. The stone had come out
of the setting and Tiffany had sent it to the uncles to reset.
The setting was four low cleats along the sides of the pyramid. The
cleats were about 3/4 the length of the sides and stopped short of
the corners. The uncles reset the stone, pushing the cleats as much
as possible. The stone was secure, it wasnāt going anywhere. Itād be
good for another 50 years.
But, there was a very slight wiggle to the stone. The seat had worn
and no matter how the cleats were tightened the wiggle remained.
Thatās when it came to my bench. My job was to flow a tiny amount of
Epoxy 330 around the underside perimeter of the stone where it
touched the seat, just to remove that tiny remaining wiggle. It was
either that or build up the seat with new metal and recut it. I
suspect that Tiffany had given my boss a budget which precluded that
much labor. So we used epoxy to take out the wobble.
So, thatās the only time Iāve used epoxy to set a stone.
Elliot
Ok another new one for me. How does one rear set an opal?
Thanks,
Eric
If the argyle mine produced more then 9 miljon carats a year (for 2011) of diamonds, where is the rarity then?
My position always has been that commercial grades diamonds are not
true De Bears are marketing geniuses! They have been able
to convince general public that diamonds are something special. They
are not. Only D(s) and maybe E(s) in combination with impeccable
clarity and perfect cuts should be considered
Leonid Surpin
Rear setting an opal or other stones. I would prepare an adequately
deep setting and carefully prepare the top edge so the stone will
not come out. Then prepare a wire, say 0.8 mm and make a ring to fit
tightly inside the setting, (for an irregularly shaped stone base
make the wire ring follow the shape of the base of the stone) Insert
stone and the shaped wire ring. Now using a sharp V graver inside
the setting raise a series of small āclawsā gently closing against
the wire ring, do one then repete on the opposite side then on the
quarters. Do 8 or more of these claws, and then go over them again
tightening them against the wire. I would suggest you practice this
process on a sample to get the āfeelā of the process.
David Cruickshank Australia
jewellerydavidcruickshank.com.au
I have used epoxi when setting opals many timesā¦ not to hold the
stone in place but to make sure the stone had a very even support
under it before setting the bezel. Once I started using this
technique I never cracked or broke another opalā¦ And to my
knowledge none of my clients have ever cracked or broken a opal I
have set this way in the over 40 years I have been doing it.
Vernon Wilson
Did I real that post right? Did Leonid imply there was a lack of
durability in opals and hence they were not LOL how
durable are natural emeralds?
Quality Opals are equal in visual impact to any other fine stone.
I have not read much here really relevant to opal setting, so lets
do Opal Setting 101 for a pendant.
Opals are not constructed from crystal structure, the stones are
made from small spheres which are easy to separate or crack.
Opal setting is a specialized skill. For me it is ten times harder
to set an opal than a round 1 carat diamond.
Opals are cut en cabachon to maximise the stone. Hence they are
often in āfreeformā shapes or cabs.
They, unlike the diamond, are not computer precision cut.
Hence the back of the opal is usually uneven!!!
It takes a long time to set an opal.
Have frequent brakes this could be very nerve wracking.
Make your bezel from.8mm thick fine silver or gold and as wide as
the stone is high.
It should be big enough to allow you to easily pass the stone
through the bezel. Opals do not like being pushed around. They can be
broken more easily than turquoise or malachite.
Now you have your bezel. You have to make the seat for the stone.
Get a strip of.8mm square wire of the parent metal as long as the
bezel.
Now the āfunā starts. Fit the.8mm wire into the inside of the bezel.
Cut to size and solder. Alloy to cool before pickling.
Now you have a bezel and a piece of.8mm square wire the shape of the
bezel that fits tightly into the bezel, this is the seat for the
stone. Push the wire into the bottom of the bezel.
Now the xtra fun starts. Place the stone with the bezel around it
face down. I use a rubber bench pin for this.
GENTLY push the wire down till it conforms to the shape of the
stone. You may need to burnish the wire back to the sides of the
bezel. This depends on how far you have to move the seat, the
deformation of the wire may pull it off the sides. This is why fine
metals are use they are malleable.
Solder the wire seat in. Solder on bail etc. Clean up and bring to
final polish and clean.
Now you have a bezel with a seat that fits your stone. If setting a
cab some filing may be needed to bring the bezel height down. This
is a metal sacrifice due to the process of getting the seat to fit
the stone.
If you have a freeform stone you need to file the bezel to the
contours of the stone. Yes metal sacrifice makes opal setting
expensive.
Put the setting on your bench pin and put in the stone. Use a bezel
pusher, for a cab use usual setting sequence. But check with a loupe
frequently. When the metal is down on the stone leave it for the
moment.
With a freeform stone start pushing from the Corners.
When the bezel is down clean up tool marks.
Burnish the metal to make it gleam, this takes TIME and louping.
TAKE TIME AND CARE AND YOU CAN DO IT!
TTFN
Richard
Opal setting is a specialized skill. For me it is ten times harder to set an opal than a round 1 carat diamond.
Over the years I have had this discussion with retail jeweler
clients. I had a price list for setting stones based on stone size.
I might charge $20 to set a 6mm round stone in prongs. The jewelers
were fine with that when it was a diamond, but would sometimes
question it when it was a garnet or even an opal. They would say, in
the case of a garnet, the stone only cost me $5, how can you charge
me $20 to set it?!? My reaction was always the same, that the value
of the stone is irrelevant to me when setting it and that it can be
more risky and time consuming to set the garnet or the opal than the
diamondā¦so really I should be charging you more to set the more
fragile stones. That usually endedthe conversation.
Mark
Richard, I disagree with you on some points regarding bezel setting
of opals.
Quality Opals are equal in visual impact to any other fine stone.
They are not equal, they are GREATER! About most opals not being
flaton the back, I almost always cut them flat on the back to avoid
these complications.I see rounded backs mostly for high end black
opals, where it has been customary to cut this way to maximize
weight (a trick which has long since been taken into account when
valuing the opals). I donāt think opal setting, if properly cut, is
that hard. I have set quite a few, mostly without problems.
Hi Richard!
Thanks SO much for the lecture. When I traveled to Spencer, Idaho, I
had picked up more than a few āopal startersā at one of the stores
there.
An āopal starterā is a piece of opal which has already been extracted
from its matrix and placed on a piece of dark stone.
The craftsman had put a layer of epoxy over the starter and said that
when I was ready to use it, go gently with 1200 grit abrasives.
Since Iām not up to bezels yet (I donāt even know how to solder
sterling yet, I just fuse fine silver), I thought to scan the opal,
derive the outline with GIMP, create the CNC code to mill out a
window from silver with a surrounding step the opalās thickness, then
utilize a cold connection to fasten the frame to the rest of the
piece.
Could that fly?
Thanks,
Andrew Jonathan Fine
Andrew,
Since I'm not up to bezels yet (I don't even know how to solder sterling yet, I just fuse fine silver), I thought to scan the opal, derive the outline with GIMP, create the CNC code to mill out a window from silver with a surrounding step the opal's thickness, then utilize a cold connection to fasten the frame to the rest of the piece
Why not take a few minutes and learn to solder? Itās one of the
first things that beginners learn to do and is an essential part of
making fine jewelry.
Jamie King,