Back to Ganoksin | FAQ | Contact

Open Back or Not


#1

I have a question that those of you that have been doing
fabricating hopefully will be able to answer. In a bezel setting
I have been taught to leave the backsheet intact (I work fine
silver or high carat gold). I also use a shiney fine silver foil
inside the bezel. I was wondering whether it makes a difference
when the backsheet is opened or if this is just personal
preference. If the item is sitting against the skin it should
reflect as if the back was closed. I would appreciate any
feedback on this. Thank you all and Happy New Year. Linda K.
Red1Eagle@AOL.com


#2

If the back of a bezel setting is open or has an opening, I feel
that it is easier for the back to tarnish although the fine
silver foil would counteract that problem but it would not
prevent the collection of collect “crud.” Crud (soap scum, body
oil, garden dirt, paint etc.) Marilyn Smith


#3

I prefer to leave the back open. This will enable you to clean
behind the stone better.If the back is closed,the stone will
still accumulate dirt,but it will be much harder to clean.With
stones that are sensitive,this may make it impossible to clean at
all.

                   S.H.

#4

I have a question that those of you that have been doing fabricating
hopefully will be able to answer. In a bezel setting I have been
taught to leave the backsheet intact (I work fine silver or high
carat gold). I also use a shiney fine silver foil inside the bezel.
I was wondering whether it makes a difference when the backsheet is
opened or if this is just personal preference. If the item is
sitting against the skin it should reflect as if the back was closed.
I would appreciate any feedback on this.

Thank you all and Happy New Year. Linda


#5

Hi Linda,

I too use closed-back bezels for all but faceted stones. The
purists among us will probably oppose this practice but as the
designer/maker, I want to be the one who controls the color of the
stones I use. The only way to do this is to use closed back bezels
and sometimes to foil-back the stones, as you already do. A
blue-green tourmaline cab in a gold bezel will become a yellow-green
tourmaline if it is not backed; pink will become peach or orange,
etc.

The only alternative that I know of is to create a fairly high
gallery for an open-backed stone. If it’s high enough, sufficient
light will enter from the back to prevent or at least minimize color
change. This is probably the most professional and traditional
method for setting cabs but it is also the most labor-intensive and
time-consuming. In the interest of controlling color and keeping
time/labor investment at a reasonable level, I prefer closed-backed
bezels.

Where faceted stones are concerned, the issue is usually irrelevant.
In a well-cut stone, light will never reach the backing, rendering
it unnecessary.

Beth


#6

Linda,

Whether the back of a setting is left closed or cut away is in
individual decision and one’s idea of how a setting should look.
There are some technical reasons to cut away backplates such as…if
you are setting a very large stone and using heavy plate…cutting
part or most of it away will make the piece lighter. If you are
setting a translucent or transparent stone, especially ones with
beautiful dendrites or plumes etc, cutting away the back will allow
play of light that can make the piece more beautiful. If you are
using light plate…say 24 or 26 ga, leaving all or most of the back
plate will increase regidity and strengthen the overall piece.
Sometimes the back plate is cut with a design just to make it look
’pretty’. In effect, there are lots of reasons to leave the back
plate alone…and lots of reasons to remove all or most of it!

Cheers from Don at The Charles Belle Studio in SOFL where simple
elegance IS fine jewelry! @coralnut2


#7

Linda, One consideration is that, with use over a period of time, the
back of the stone can become dull due to an accumulation of dirt,
soap film, etc. This stuff can seep in under the edge of a bezel. It
the back is left open it can easily be cleaned periodically. It you
close it, there is no effective way to clean it. This is, of course,
only important with stones that are translucent or transparent.

Joel Schwalb
@Joel_Schwalb
www.schwalbstudio.com


#8

Linda,

I forgot to ask in my other posting, what is the shiny fine silver
foil inside the bezel for? Is this with faceted stones? Dale


#9

Hi Linda,

While I am certainly not one of the experts on this list, I will
venture to answer your question. Since I have not yet been working
with faceted stones, I will also limit my answer to bezel setting
cabochons and leave any discussion of faceted stones to those more
knowledgeable than I.

Whether to leave the back open or closed depends upon a number of
factors:

  1. Transparency or translucency of the stone. Reflections from the
    closed back behind a transparent or translucent stone can interfere
    with or obscure the characteristics of the stone. An example would
    be a closed back behind a rutilated quartz crystal cabochon.
    Reflections could obscure the rutiles and make them less visible.
    Another example would be a translucent opal. Reflections from a
    closed back could interfere with the fire of the opal. However, a
    properly textured and/or patinated background behind such stones can
    also be used to create some interesting effects and enhancements to
    the characteristics of the stone. For example, a black patination
    behind a translucent opal can be used to make the fire stand out and
    more consistently without concern for what background effect
    different clothing may have. One note of caution here is that if
    not properly done, this can look as though you are giving a fake
    appearance to the properties of the stone.

  2. Weight considerations. In a larger piece, leaving the back
    closed will add more weight to the piece. This is generally
    undesirable from a comfort standpoint of the wearer as well as the
    fact that it adds cost to the item, especially when working in
    higher priced metals such as gold. In smaller pieces, leaving the
    back closed will also add some weight which can be desirable in that
    it can give the piece a more substantial feel.

  3. Design considerations. Sometimes whether to leave the back open
    or closed is best determined by the design and what kind of look you
    want your work to have. A closed back can give a piece a more
    elegant look, even if the wearer is the only one who will see it.
    Sometimes you may want the back of the stone visible such as if it
    is a particularly interesting stone. An example might be a piece I
    did recently with an intarsia cabochon. I left the back open
    because I wanted people to be able to see that what was visible from
    the front went all the way through the stone (I did not use a
    backing piece for the intarsia). I found that most people who
    looked at it were surprised by that fact.

I hope this gives some helpful insights to you.

Best Regards,
Dale


#10

Happy New Year to you too, Linda.

First, I’m going to assume that you’re using a faceted stone for
this bezel setting. This is where the study of gemology comes in
handy. When a gemstone is faceted properly, light will enter the
stone through the crown (the top portion), bounce around inside,
hopefully off the pavilion, and exit back through the crown to the
viewer’s eye. This is due to the stone’s crown and pavilion angles
being cut in harmony with the stone’s critical angle. For this
reason alone, opening or closing the back of the setting will have
no effect on the stone’s interaction with light, and therefore, it’s
appearance to the eye. From this you’d think that an
open or closed back would have absolutely no effect on the stone’s
appearance.

However, oils and grease from our bodies and the things we handle in
our day-to-day affairs can and will be attracted to the stone,
especially on the pavilion of it. This very different substance
(different from the gemstone, that is), when attracted to the
pavilion, actually changes the critical angle of the stone (makes it
much larger) and will cause a phenomenon known as “unplanned light
leakage”. This means that light will enter the crown and, instead of
bouncing around the pavilion and exiting back through through the
crown, it will exit through the pavilion, thereby reducing the
brilliance of the stone. This is why gemstone jewelry loses it’s
sparkle when dirty and regains it when cleaned.

Even bezel-set stones will attract dirt, oils and grease to it’s
pavilion, no matter how closely the bezel is set to the stone. for
this reason, I recommend that, whenever possible, you leave at least
a small open area in the back of your setting to facilitate cleaning
so that your gems may indeed sparkle forever.

James S. Duncan, G.G.


#11

I generally make my bezel set stones open backed,particularly when I
am setting a large freeform. Sometimes during the fitting process, the
stone gets stuck in the bezel. If the back is open, you can apply
pressure to the back of the stone through the opening to pop the
stone out.

Regards
Milt Fischbein
Calgary, Canada


#12

I haven’t been following this thread too closely so I apologize if
someone has said this before, but if you use an open back in a
pendant or pin the color of whatever the person is wearing will
determine the color the stone looks (in other words it is out of your
control how the stone appears) and if it is in a ring it will be
backed by the person’s skin color. This, of course, mostly applies
to cabochons and not faceted stones as any well faceted stone
shouldn’t allow that much of the skin color come through. Also, I
hope that those of you who choose to use foil backings are informing
your customers about that, as it can alter the stone’s appearance
over time and effect future repairs. Remember you can never disclose
too much.

Daniel R. Spirer, GG
Spirer Somes Jewelers
1794 Massachusetts Ave
Cambridge, MA 02140
617-491-6000
@spirersomes
www.spirersomes.com


#13

Depending on the piece and the “look” you are after… If I decide
on a closed back setting I generally drill a small hole in the
center or off to one side. This is to facilitate removal of the
stone during setting should problems arise.

It’s also so that the next person to work on the piece that may have
to remove the stone doesn’t turn the air blue cussing me!

There have been a few exceptions to this for design or aesthetic
reasons – but not many.

Brian P. Marshall
Stockton Jewelry Arts School
Stockton, CA 95209
209-477-0550 Workshop/Studio/Classrooms
instructor@jewelryartschool.com


#14

All, I am a stone cutter and a jewelry maker. To me all stones
facetted in cuts to make the stones more internally brilliant should
be set in open back mountings. The more light that enters the stone
the better.

Cab stones are a different matter. After listening to many buyers I
have found that there are several reasons for open back settings in
cabs and several reasons for closed backs. This makes a difference
in my decision to invest my time in the finishing of the back of a
cab.

Open back - show off the design on the back of the stone.

-   	better show the translucency of the stone.
-  	to get the feel of the stone on the skin of the wearer.
- 	for wire wrappers to show a fully finished product.
-  	to save metal and weight in production.

Closed back - to make a stronger setting.

-  	to make designs on the back of the setting.
-  	easier to produce

Gerry Galarneau - In the final rush for Tucson 2004, Gem Mall Booth
111 Jan 31 - Feb 13. More beautiful custom facetted stones and cabs
from all over the Earth.


#15

Gerry, Faceted stones reflect from internal surfaces and do not
require open backs. To suggest otherwise is to say that a stone set
in a tube setting will not sparkle. Au contraire! A PROPERLY cut
stone is based on the assumption that the refractive index of the
mineral will determine the angle of reflection of the stone. This is
EXACTLY why windowed stones don’t sparkle ! Ron at Mills Gem, Los Osos


#16

The only major reason that a bezel setting should have an open back
… and more so for faceted stones is to be able to clean the
ring/stone area easily. If it is closed, when you go through a
cleaning cycle , it would be very easy to trap dirty water behind
the stone … this will greatly affect the look of the stone .

Also, how would you like to try and clean a ring that was worn for a
year and the back was sealed, but the stones look bad because of
dirt inside the bezel area… I have seen this happen and Its’ not
fun.

Daniel Grandi