Hi Orchid Experts, has anyone looked at the text accompanying the
Indian Mughal jewellery exhibition at the Metropolitan Museum of
Art, specifically the reference to the technique “kundan”? I quote:
“Unique to Indian artisans was the gem-setting technique known as
kundan, in which pure (24-carat) gold foil is fused at room
temperature around This resulted in unparalleled freedom
for jewelry artists to realize their designs.”
Wow! Does anyone know how to fuse 24 carat gold at room temperature?
46 years of making jewellery tells me this is impossible, but hey,
what would I know, I’m not an academic curator of exhibitions nor an
expert in Mughal jewellery techniques. However, if there is a way to
fuse any carat gold at room temperature, I’m definitely interested.
I’ve always dreamed of being able to hold components together with
my fingers while I soldered them together… (sigh)
Oppi Untracht’s most recent book, Traditional Jewelry of India, has
a complete description of “kundan”. …as well as many other
traditional Indian techniques. It is as encyclopedic as his Concepts
and Technology.
Rex, Pure (999) gold can be fused or welded at room temperature.
Using this principle, folded strips of fine gold are packed around a
stone between the stone and the surrounding metal and burnished down.
Page 614 of Oppi Untrecht’s "jewelry concepts and technology"
explains it in more detail. Jerry in Kodiak
This exhibition was first seen in London and had most jewelers and
goldsmiths rolling around with laughter because the catalogue was so
inaccurate. Its bad technical language, the overweening
descriptions, wrong designations of the stones and materials and
complete misunderstandings of technique I have yet to come across a
catalogue that I so longed to throw across the room.
The pieces, however spectacular, seem to have been collected on the
basis of how expensive they were to acquire rather than curatorial
interest.
I know my jaw dropped at the complexity of some of it, at the sheer
daring of the makers and designers and the skills they required to
cut and polish the stones - but the exhibition taught little about
the politics of the jewels and the manufacture of them.
Kudan is the method I was taught of cutting and polishing a stone to
fit a cell of metal - the opposite method of western jewelers and
very time consuming in itself. It’s then held in place (set) by
holding it in place and pressing gold leaf into the spaces then
burnishing it down - rather like wet paper - so that it holds the
stone in place. It will work! But… it takes forever. Remember how
thin gold leaf is and how much you’ll have to burnish in order to
form even a thin layer of metal. You have to press down very hard as
well, using an agate burnisher lubricated with spit!
Even a small piece of this type requires hundreds of hours of work.
"Unique to Indian artisans was the gem-setting technique known
as kundan, in which pure (24-carat) gold foil is fused at room
temperature around This resulted in unparalleled
freedom for jewelry artists to realize their designs." Wow! Does
anyone know how to fuse 24 carat gold at room temperature?
Hi Rex, Well, if you press 24k gold foil against itself hard enough
then it packs together and appears to bond (burnishing helps),
certainly it can bond if struck hard enough - unlikely when setting
however. But if the gold is not foil, but a spongy mass then it can
be packed hard enough together that it bonds. This is how dentists
used to fill cavities, by ramming spongy gold nodules into the hole
and packing it up tight. Ow. You cn sometimes runa corss this brown
looking spongy gold bits in old dental tool kits. best Charles
I recently had the privilege of watching this process during a visit
to Rajasthan. The tiny gold foil paillons are pressed firmly around
the stone, then burnished to look like a bezel. The stones are
usually added around areas of champleve enamel. So, not fused in the
usual sense of the word.
I would be very interested to know how long that particular
exhibition will be showing, as I will be visiting New York next April
to teach enamel workshops at the Enamel Guild Conference.
Dear Rex Try and have a look in Untrachts “Jewelry”. He describes the
process very accurately under stone settings. I’m not sure he uses
the word " Kundan", but the process definitely is the same. Haven’t
tried it myself.
Hi Charles- How interesting!! How is this “spongy gold mass” formed?
How could you make it? Thanks in advance, Krystina in cool, spring
Santiago de Chile
Wow! Does anyone know how to fuse 24 carat gold at room
temperature?
Rex perhaps I can help. When I was in dental practice,I would
occasionally insert a filling known as gold foil. Basically this
consisted of building up a mass of pure gold within the cavity by
adding and cold welding small pieces of 24K gold in the form of
foil. Among the many unique properties of gold (pure) is it’s
ability to weld to itself without heat (therefore at room
temperature).
The gold pellets which we would plug into the cavity consisted of
very thin foil rolled into a ribbon, and then cut into pellets.
(Some operators would use the ribbons as such). These pellets would
be annealed just prior to plugging, and then carried on an
instrument to the tooth, There were several different types of
pluggers used, some simple hand pluggers which were spring loaded,
and the one I used was air driven by a simple air pump. The filling
was overbuilt, burnished well, and then contoured to shape. Usually,
one would obtain these pellets already to use. When I first started
out, gold was $35/oz, but because this was such a highly skilled
technique, and rather time consuming, it necessitated a rather high
fee. Unfortunately, this technique is seldom used today, but if
properly done, it probable the best restoration in the dental
arsenal.
The basic procedure can be used for the setting of a stone, but I
have never tried it myself. If, however, you would like a more
detailed direction please feel free to email me at @JoJu428
PS I still have my plugger and use it in setting small stones. It
provides a very gentle and adjustable thrust and enables a fairly
rapid setting tool. Because of the almost obsolescence of this
procedure in today’s dentistry, it may be possible to obtain this
device in a used dental supply co., and I recommend it highly as a
setting tool.
Dear Jo, thank you for the info about pure gold and its use in foil
form in dentistry. Would this work on the same principle as kum boo?
Kind regards, Rex
There was another process once offered for “cold Joints”.
Dental gold foil as used in dental fillings was dissolved in
gallium. Gallium seems to wet everything including plastic and people
fingers. The resulting paste was pressed into place and would
solidify for a permanent bond. It was once tried for fillings and
electrical connections.
Gallium, the metal, is used (was is probably more correct) in doping
transistors. It has the unique characteristic of expanding on
freezing. Interesting metal.
I believe that Alcoa has a data sheet.
Bill in Vista
Hi Jenny Gore, thank you for the re your personal
experience. Perhaps kundun/kundan works on a similar principle to
kum boo. I know from experience how malleable fine gold can be, but
I’ve never succeeded in making thicker layers adhere with a molecular
integration, no matter how hard I burnished. If there are nooks and
crannies, undercuts or other variations, it is possible to burnish
the gold into these so that there is a physical adherence, but it’s
not as permanent as genuine fusing or soldering. At least, not in my
experience…
Good luck on your enamelling trip to NY. The Mughal Jewels
Exhibition will be at the Met until Jan. 13th 2002, then it goes to
the British Museum after a few other venues in the States. More on
the Met website www.metmuseum.org/
Hi Rex, Yes, gold can definitely weld to gold at room temperature.
All it takes is cleanliness and pressure and the more of both the
better. It doesn’t even need to be 24 K. Natural nuggets may be
formed by accretion. There is a report in the mineralogical
literature of an old gold coin lost in Alaska (if memory serves
somewhere in the late 1700’s), which, when it was rediscovered, had
flakes and little buds of new gold accreted to it. And again if
memory serves, the “Gold Bulletin” a year or so ago published a paper
on fusing gold to gold at room temperature in a process in which a
strip of gold backed with an explosive was fused to another strip of
gold by the pressure of the detonation. I doubt this would lend
itself to gem-setting.
I’m not Charles, by a long shot, but something “clicked” from his
description and something I recently read. The October issue of AJM
Magazine (thanks, Suzanne!) had an extensive article about refining
for the jeweler/metalsmith. One of the latter stages of refining gold
apparently leaves one with a mass of spongy pure gold, which is then
melted and poured into the final ingot or shot form. Could be this
stone setting process is a natural evolution resulting from the
refining techniques being used???
P.S. The article even has a photo of the gold in this “spongy”
state…
All the best,
Dave
Dave Sebaste
Sebaste Studio and
Carolina Artisans’ Gallery
Charlotte, NC (USA) dave@sebaste.com
Dear Jo, thank you for the info about pure gold and its use in
foil form in dentistry. Would this work on the same principle as
kum boo? Kind regards, Rex
Rex, The technic of “adhering” pieces of metal (either the same
metal or different ones) in the Kum Boo process depends upon
increasing the velocity of the molecules with-in the pieces by the
addition of some heat and obtaining intimacy of contact by
burnishing well. The way I think about how the adherence occurs is:
some of the molecules at the surface of each piece escape into the
surface of the opposite piece and this minimal exchange of molecules
at the surfaces results in the join. It is not truly a fusing of the
pieces.
The welding of pieces of gold in the pure state with the elimination
of any contaminates (by annealing just before) takes place at room
temperature, but with a light thrust or pressure delivered over
multiple points on the surface. This is repeated many times until
the desired mass is accomplished.
I don’t know if the same welding process can be accomplished with
fine silver if properly prepared, but I would think it indeed might
work. I was told many years ago that this was a unique property of
gold, but I am beginning to question it. Might be worth an experiment.
HTH Joe Dule