I have been trying to finish a job which I started in Argentium
because I really enjoy working with the material for normal
fabrication and casting. I am using the 950 older formula as I have
plenty of it.
My older, Thompson leaded transparent enamels are clouding up badly
in the pique-a-jour work I am attempting. They look almost opaque
when about 1mm thick. I am using the powdered enamel, and washing it
well before using. I am firing two firings until sugary, then the
final filling is being fired until Isee a glossy finish. I am using
new mica, over steel mesh. I am using a propane-oxygen torch,
although I also have a digitally controlled kiln. I can’tget it to
clear and become transparent. I have tried (on scrap Argentium) to
over fire, but it makes it more opaque. I really need a mid blue for
theseearrings! I have tried (all Thompson):
CT-120 ultramarine TR
TCT 340 Bluejay Tr
313 Chinchilla Tr
TC-241 Larkspur Tr (this is about the shade of blue I want)
TCT 113 Dresden blue Tr
All of these are not going transparent! What am I doing wrong? How
can I geta clear stained glass window effect?
Joris- As you are throughly washing your enamels the only thing I
can think of is that the enamel is too fine a mesh. The coarser the
grain the clearer the enamel. When I do pique a jour I grind my own
lump enamels to a fairly coarse mesh and wash. I fire all the way to
glossy on every layer.
If you are wet packing be sure to use distilled water.
Argentium is not usually a suitable metal for enameling, although
there is a lot of experiementation going on right now with different
argentium alloys, and some people are succeeding.
The chemical composition of the enamels (which is glass combined
with various oxides to give the desired colors) reacts differently
to the chemical composition of various metals.
Generally, enameling is best done on copper, fine silver, pure gold,
sterling silver with the fine silver raised by repeated pickling,
certain alloys of gold, steel and glass (with enamels developed to
work with the co-efficient of expansion for the glass).
Probably the non-silver part of the argentium alloy is reacting
negatively with the enamel. You might try an undercoat of high fire
clear enamel, or an opaque white as a base to separate the blue
transparents from the argentium. I don’t know if that will work, but
it might provide a barrier against reaction from the enamels to the
argentium. You might try facing the argentium with a thin layer of
fine silver where you want to enamel.
I have never tried raising the fine silver in argentium, but you
might want to give that a try. With sterling, you need to heat with
a torch, pickle, rinse and repeat about 5 times or more. You will
see a thin layer like a shell of fine silver on the metal.
Some colors are generally more sensitive when enameling, but blues
tend to be stable.
My best work was with Schauer high L enamels which I used as follows.
I used an enamelling kiln, electrically heated capable of 1000
Deg C.
this gave me an oxidising atmosphere, essential for HLE.
It was fired onto fine silver or fine gold sheet made up into
little cells with 3mm high sides up to 50 mm in dia, 8/1000in thick
The enamels were placed as lump enamel fired up to 950 C.
Was water clear at that depth, as the metal was chased with a
polished hammer to give a diamond milled effect.
So., your problem is best solved by running a controlled trial., 1.
dont use a torch. Use your kiln.
fire the enamel onto fine silver sheet ie 999 grade. say 5/1000
in thick, ditto fine gold. If you have it in stock you can use fine
silver or gold enamelling foil,
Repeat onto your argentium silver to the same temp. in your kiln.
Compare results and let us know whether it was the metal, or the
enamel.
Enameling transparents on Argentium Silver by firing in a kiln has
been a difficulty for a long time. Ronda Coryell made the fabulous
discovery that torch firing AS 935 works wonderfully. She and I
discussed it, and came to the conclusion that the reducing
atmosphere created by the torch flame must be the reason for success
with torch.
In the meantime, having done many many many many many kiln trials
under various conditions, I had given up on enameling on AS 935, and
begun investigating enamel on AS 960. One man in Denver, CO (whose
name escapes me at the moment—sorry!) has had success with AS 960,
so that gave me hope. After more trials, working with my friend
Joanne Conant, we figured out that Klyr Fire clouds enamels on
“fresh”/unfired/not torched or pickled AS 960. Klyr Fire is no
problem if the AS 960 has been depleted.
So, my suggestion is that you try some test fires on scraps in the
kiln, and pay attention to the above “rules” about Klyr Fire. Joanne
and I have found that some blues work better than others. We have
primarily tested Thompson unleaded, so I don’t have any info for you
about the old leaded blues.
Also, I am wondering if it is actually AS 950? I have some AS 970
that was on the market briefly, but I do not remember the we ever
had AS 950.
Please DO let us know how these trials go!
Cynthia Eid
Thank you Cynthia for sharing your experiences with Argentium 935.
I found your comment about an reducing flame being very interesting,
as I was using a iron shield to keep the torch gases from the work,
possibly depriving it of the benefits of a oxygen depleted
atmosphere around the piece being fired.
I did make a mistake in my original posting-I was using the older
Argentium 930, not 950.
You mentioned that you stopped working with 935. I’d be very
interested in knowing why you chose not to keep working with it, and
why you are focusing on 960.
Also you mentioned depletion gilding. I still do this before
enamelling on old fashion copper-based 925 before enameling by
repeated heating and pickling. I did not realize you could do this
with Argentium-I thought that you would end up with a layer of
germanium-in fact, is this not what happens when you heat Argentium
normally? Is it not that layer of germanium which protect the copper
portion of the alloy and keeps the fire scale away?
I will try some more experiments and post any successes that I have.
I will try a reducing flame to see if that helps. I have received
some other feedback which I will try as well, and get back with my
results. Thank you to all those who have replied and are helping me
with this.
A ha! Thanks Cynthia Eid for the info. I wondered if it just might
be the metal.
Although Rhonda Coryell has had some success with torch enameling on
AS I would not use a torch for plique a jour but do it in the kiln.
Direct flames on glass. not so good.
I’ve always done PAJ on fine silver.
I’ve been experimenting with and using Stuller’s Continuum silver
with various techniques and just love the metal. So far no negatives
at all in working this metal. I plan on starting to try enamels with
it. II’ll do a quick experiment doing PAJ on it. 'll let all yall
know how the enameling experiment works out.
I do quite a bit of enameling, and for jewelry, (mostly cloisonne
and some plique a jour), I always use fine silver–18 gauge. I am
wondering why some prefer argentium to fine silver. Alma
In regard to discussing the relative merits of 930, 935, 950, and
960, I thought it might be interesting to note that in Israel, all
filigree was always done with 960 sterling. It has the tremendous
advantage of going white (not black) when annealing, which is the
traditional way to clean all the teeny tiny pieces from any grease,
dirt, etc. they may have picked up when being formed.
I have always enameled (cloisonne) on copper with either a clear or
opaque-white base on front and back. I think copper has better
expansion/contraction properties than silver (?). If I wanted
transparents on gold or silver, I used foil for those areas. You can
build up very subtle shading with great depth over the opaque
white" I usually had around 10-20 firings (thin layers) on a piece.