Loving Argentium sterling!

I’ve been making quite a lot of cufflinks recently, experimenting
with etching to create my designs. I decided to try Argentium
sterling for one particular pair, which involved me etching a
"Spitfire" aeroplane design into the silver, then saw piercing it out
and fusing it onto another piece of Argentium sheet to which I’d
given a hammered texture. I’ll blog about it later hopefully.
Incidentally, it etched beautifully with ferric nitrate. I had pieces
of standard sterling, Britannia sterling and Argentium sterling (all
from Cookson’s). The Argentium seemed to produce the best etch out of
the three.

I’m MEGA-impressed with how easy it is to fuse, and how there’s no
firestain whatsoever!!! I just used flux for the joint and any
discolouration was easily removed in the pickle. I successfully
hardened it in my domestic oven after polishing, then removed any
discolouration with pickle.

The only thing I found challenging, was that it didn’t seem to want
to take a polish as readily as standard sterling. Presumably, this is
to do with the fact that a layer of germanium has been brought to the
surface whilst being heated, which was then oxidised to germanium
oxide which is harder than the sterling surface would normally be.
Is there a polishing compound which anyone can recommend for
polishing Argentium to a high shine?

I’ll definitely be using Argentium on a regular basis now, and hope
that my supplier starts stocking more products very soon!

Helen
UK

Helen, If you would coat the entire surface with flux before fusing,
you will eliminate the problem of the germanium oxide forming before
you you want it to. I have also used firescoff, Cuprinil, Boric
Acid/Alcohol, etc. You are not having to protent against firescale,
just protecting the surface while fusing since you are firing at
extreme temperatures for the metal. If you don’t, the germanium oxide
surface builds more than you want or need it to. I find that
Argentium polishes better than Sterling. I then put in the oven at
212 F for 1 hour when I am finished with the piece.

Ronda Coryell

Hi Helen,

I am thrilled to hear how much you are enjoying working with
Argentium Sterling! I am mystified that polishing was difficult.
What polishing compound were you using? The one suggestion I have is
to apply Goddard’s Long Shine Liquid to a clean buff for the final
polish. I rarely put a high polish on my work, so I have not done
this, but one other user told me about the practice, and it makes
sense to me, since in addition to polishing compounds, the Goddard’s
Long Shine products contain chemicals called thiols, which act as
extra “insurance” against tarnish.

Best wishes,
Cynthia

Hi Cynthia,

I am mystified that polishing was difficult. 

I think Ronda’s hit the nail on the head. I was only fluxing the
joint to be fused, rather than the whole piece. This apparently
means that I was building up the layer of germanium oxide too early,
making it difficult for me to get the high polish I wanted. It makes
perfect sense. I’ll carry on coating the entire piece with Prips -
which I do when using standard sterling - and that should solve the
problem nicely. I’m not sure where I got the idea from that it was
okay to just flux the joint. I must have assumed it rather than read
it.

I’m currently using Yellow Dialux and Fabulustre polishing
compounds, but have been recommended others to try. I think going
with Ronda’s “flux the whole piece” advice would be the first thing
to try before buying new compounds and wheels.

I will get a Goddard’s cloth as the final “insurance”, as Peter
Johns was saying that the thiols actually chemically, and therefore
permanently bond to pure germanium. Tests were apparently done to
see whether there was enough free germanium at the surface to bond
with the thiols and therefore give the desired protection against
tarnish, and it was shown that there was indeed sufficient germanium.

Thanks for the advice Cynthia. I can see me using a great deal of
Argentium sterling in the future! I can see the fact that you can
fuse it instead of soldering it, being a very useful feature in
situations where even a small amount of visible solder might look
ugly, such as attaching wire embellishments to surfaces, etc.

Helen
UK

Hi Ronda,

If you would coat the entire surface with flux before fusing, you
will eliminate the problem of the germanium oxide forming before you
you want it to. I have also used firescoff, Cuprinil, Boric
Acid/Alcohol, etc. You are not having to protent against
firescale, just protecting the surface while fusing since you are
firing at extreme temperatures for the metal. If you don't, the
germanium oxide surface builds more than you want or need it to. 

Ah, that makes perfect sense. I did get the sense that I’d built up
the germanium oxide layer too much, but hadn’t considered that in
not fluxing all the metal (just the joint for be fused), I’d actually
built it up too early. That should solve the problem and make it
much easier to polish before hardening in the oven.

Many thanks Ronda. BTW, I very much look forward to watching your
DVD’s on the subject, which Peter Johns highly recommended to me. He
said you’re doing amazing things with Argentium, so they’re
definitely worth watching.

Thanks again Ronda.

Helen
UK

Helen, your statement

I successfully hardened it in my domestic oven after polishing,
then removed any discolouration with pickle. 

confused me. I would think that putting a piece in an oven after
soldering would be the same as annealing it, which is softening, not
hardening. And wouldn’t it make more sense to pickle after soldering
to clean the surface, then harden or soften, and lastly polish? Or
am I misunderstanding what you’re doing?

Mary Partlan
White Branch Designs

I know I will not be the only respondent, but here goes. Argentium is
a different beast. The Germanium alloy allows for “manipulation” of
the metal, that when heated for a sustained period of time dependent
on the temperature, actually brings the Germanium to the surface, as
I understand it, and creates a “hardness.” Hope I’ve said this
correctly. It is the “first” precious metal that I’ve worked. I have
enjoyed my experience to date… lot to learn though!!!

Hi Mary,

I successfully hardened it in my domestic oven after polishing,
then removed any discolouration with pickle.
confused me. I would think that putting a piece in an oven after
soldering would be the same as annealing it, which is softening,
not hardening. And wouldn't it make more sense to pickle after
soldering to clean the surface, then harden or soften, and lastly
polish? Or am I misunderstanding what you're doing? 

Read the following article by Cynthia Eid:

Argentium sterling silver (and to a lesser extent, ordinary sterling
silver) can be hardened by a process called heat hardening or
precipitation hardening. In the case of sterling, it involves two
steps, firstly heating to a red heat for a certain amount of time
(preferably using a kiln) and then quenching at the right moment, to
freeze the metal particles in the state required, then secondly,
heating in a kiln to a lower temperature of about 230 degrees
Celcius (from memory so I may have it wrong) for a couple of hours.
If I remember rightly, this is to do with certain particles migrating
to the surface, which otherwise would take many years at room
temperature - hence using an oven to speed up the process. With
Argentium, apparently the first step is not needed, and you can just
use your domestic oven to effect the hardening process. The above is
vastly simplified and can be explained much better by any of our
metallurgists.

Argentium sterling contains a small amount of a metal (well strictly
a metalloid, meaning it exhibits some metallic and some non-metallic
behaviour) called Germanium. Heating brings the germanium layer to
the surface where it bonds with oxygen to form germanium oxide. This
protects the piece from tarnish and is also harder than an ordinary
sterling silver surface. The germanium oxide layer will form at room
temperature, but heating accelerates its formation, and of course
the oven heating is also hardening the piece at the same time.

The temperatures involved in the hardening process, ie those of a
domestic oven, are nowhere near high enough to anneal the metal and
make it soft, and of course do I pickle after soldering. The
hardening process in the oven can cause some slight oxides to form
on the surface, which can then be removed by a brief spell in the
pickle.

However, Cynthia’s article says it all much better than I can, but I
hope this clears up any misunderstanding.

Helen
UK
http://www.hillsgems.co.uk
http://helensgems.ganoksin.com/blogs/

Hi,

Here is a link to an article about Argentium Sterling that I wrote,

It gives an overview on working with AS, and talks about how an oven
can be used to harden AS, and that it may discolor from the process,
requiring pickling afterwards. Polishing is done before heating,
because the heating also increases the tarnish resistance of the AS,
by building up the germanium oxide surface.

Cynthia