Experimenting with granulation

Hello all,

I am experimenting with granulation for the first time with silver. I
have obtained some gum arabic, copper carbonate and some black copper
oxide. Also I have charcoal blocks on order. I would appreciate any
ideas and suggestions that could help me to understand the process
more clearly.

Thanks in advance
Richard Whitehouse, UK

Richard,

I do not know about gum arabic, copper carbonate, or black copper
oxide. I have successfully granulated with fine silver and I followed
a multi-step process similar to the one outlined by Ronda Coryell in
her DVD The Art of Granulation. There are many processes to it so
maybe you will find out more specifically what you need help on once
you start doing it. I highly recommend Ronda’s video. There is also a
wonderful tutorial in the Orchid articles by Sandra Buchholz. The
glue-flux mixture needed for fine silver is a specific proportion of
hide glue, yellow flux and distilled water. Klyr-fire glue I have
heard will also work, as well as other things. Granulating with gold
is somewhat different. I really want to granulate with 22 K gold
right now, the problem is, my life savings will only buy enough gold
for half the granules I need!

I used a beehive, or trinket kiln and coated the backs of my pieces
with yellow ochre.

Actually the latest pieces I forgot to coat with ochre, and it was
more difficult to accomplish. I just realized later that I never
coated them. The home page on my site has a picture the latest
earrings. I just need advice on final finishing. A local jeweler
friend sandblasted one of my pieces and it looks really cool.
Otherwise, the flat shiny part looks slightly blemished and
polishing techniques that usually work great can mess up the
granules.

OK have fun
Connie

I do not know about gum arabic, copper carbonate, or black copper
oxide. I have successfully granulated with fine silver and I
followed a multi-step process similar to the one outlined by Ronda
Coryell in her DVD The Art of Granulation 

I have never seen the DVD by Ronda Coryell, and granulation does not
excite me as an art form, but I am familiar with the technique.

To Richard: gum arabic and copper carbonate is all you need. The rest
is practice.

Granulation is based on the observation when copper is added to gold
or silver, the temperature of resulting alloy will be lower than
original alloy. That is only true up to either 24% or 28% of the
copper. I do not remember exact number, and I am too lazy to look it
up.

Copper carbonate, if heated with reducing flame, would convert to a
pure copper. Pure copper in contact with gold or silver would form a
solder with a lower melting point, and that will secure the granules.

Gum arabic holds everything together, while the process is going.

That is granulation in the nutshell.
Leonid Surpin.

Hi Richard,

I’m not sure what in particular you are looking for so I
apologize if this is an empty response. However, if you are looking
for a general overview of the theory and technique of granulation,
there is a wealth of in the ganoskin.com archives. Just
do a search for “granulation” and you will find lots of material. In
particular though, the most helpful will most likely be:

“Some Notes on Granulation” by Charles Lewton-Brain

and

“Theory and Practice of Goldsmithing–Granulation”

Hope that helps!
Erich C. Shoemaker

Lapidary Journal/ Jewelry Artist June 2001 “Granulated Dome with
Rpousse Bail” in two parts by Whitney Abrams

might be a good place to start.

KPK

To Richard: I find that I like something stickier than gum arabic and
that is why I use a liquid hide glue instead.

Ronda Coryell

I also recommend Ronda Coryell’s DVD on fine silver granulation for
its excellent and comprehensive presentation on fine silver fusing.
However, when copper is used, you are doing "eutectic soldering"
instead of fusing and use different techniques. A kiln is not needed
to bring the back piece up to melting temperature and you can use a
back piece that is thicker than the height of the granule. One
problem I had was that the copper coating (copper plate or copper
carbonate mixed with the glue) often did not completely alloy and
when I used depletion gilding to remove the copper, it often weakened
the bond and granules would fall off.

One solution to this problem is that if the design is first fired on
a thin sheet of steel about half of the copper will be used to
"eutectic solder" the granules together. With glue but without
adding more copper, when this granule unit is then placed on the
back sheet and heated to a “solder flash”, all of the copper is used
up andforms a tight bond.

Use a solderite board instead of charcoal for any granules under
1mm. Sprinkle about 30 same-size fine silver wire clippings on a
flat solderite board. Use a small flame to ball the wires. When all
of the wires are melted to balls, tilt the board over a container to
remove them. I use a Pyrex glass container without water. Many
authors promote the use of a charcoal block - sometimes with channels
or holes dug in or tilted so granules roll off to a dish of water.
However, all of these techniques take more time, the charcoal
degrades with each firing, and when the board is tilted, many of the
granules roll off the board before the granule is completely round.

Also, check the archives for more on granulation.

Hope this helps.
Nancy
www.psi-design,com