I make hand woven chains using fine silver 24 and 26 gauge. I get the
wire from a reputable source, and it comes on a spool and is labeled
"Fine silver" However, to my dismay, I find that over a period of
time the chains are tarnishing. I used a Sunshine Cloth to polish
them, and the chains left huge black marks where I drew them through
the cloth—really black. After polishing with the cloth, and
removing the residual polish the chains are now bright and free of
tarnish.
I tested the fine silver wire by heating it with a torch. It acts
exactly like fine silver. It does not darken in the least from the
torch.
Also, after I finish making the chains, and drawing them through a
draw plate to even it out, I anneal them to restore them to a
flexible state. The silver stays bright, does not darken from the
heat of the torch.
However, over time the finished chains are all turning yellowish and
tarnishing? What would cause this? I am really puzzled.
Maybe you have a source of sulphur near where you live. The
seashore, lots of road trafffic, or something else produces enough
sulphur to attack your chains.
I tumble polish my chains on a regular basis. Its seems that the
hardened surface is better at resisting tarnish than an unhardened
surface. On occasion I use Wrights Silver Polish (a pink paste) to
clean evverything. Mild but effective.
I would blame sulfur as either hydrogen sulfide or sulfur dioxide. A
lot of homes have been built in recent years with gypsum drywall.
This really happened a very lot during and after the last
homebuilding spree. These used a lot of drywall from China which has
caused a lot of household environmental problems.
My house which was built almost 30 years ago ha never showed the
problem. My youngest daughters" house about 7 miles away about 20
years younger tarnished silver while you watched.
In Portland you may have some pulp paper mills or maybe just one of
your volcano neighbors to blame!
Fine silver tarnishes in the presence of sulfur–that is how we get
patinas on it. Tarnishing is usually slower than for sterling. There
is probably something in your environment that is causing the
tarnish, such as off-gassing plastic, paint, varnish, or air
pollution. You can try using anti-tarnish strips or applying a wax
or other protective coating to your work. You can store your work in
plastic bags, but make sure that the plastic of the bags does not
contain sulfur. Some plastic bags will cause tarnish on your pieces.
Why do you think fine silver will not tarnish or is somehow resistant
to tarnishing? It is the silver combining with sulfur compounds that
causes tarnish. All high silver alloys will tarnish. some are
somewhat slower than others but they all will do so.
However, over time the finished chains are all turning yellowish
and tarnishing? What would cause this? I am really puzzled.
Silver Sulphide. Converted on the surface from contact with sulfur
through skin contact or in the air. The are dips that can help;
check the archives. Plating may be a possibility; I’m sure someone on
the list is more familiar with plating chain-mail.
Fine silver tarnishes in the presence of sulfur--that is how we
get patinas on it.
I’m new to precious metals, this will be an issue for me as I have a
sulphur allergy (fortunately not a life threatening one), so is
there a product I can use to blacken silver that does not contain
sulphur?
Regards Charles
P.S. I apologise for my spelling of “sulphur”, I’m an old dog and I
don’t like the new spelling.
I think you are misinformed about the properties of fine silver.
Fine silver will tarnish - it just tarnishes less quickly then
sterling. Your heat treating tests you mention are very sure
indicators of fine silver.
And just to get this off my chest Argentium can also tarnish and
stainless steel can rust.
Does anyone know how we tell which plastic zip lock bags do not
contain sulphur ? Ones we can store silver in to help prevent
tarnish. How about the ones sold in jewelry supply shops especially
for stones, etc. I would prefer not to have to buy all types and
test them as this would be a bit expensive as all those types of
items are imported into Bangladesh and not cheap.
Sharron in now hot, hot, hot Dhaka where the heavy rains are tearing
the leaves off the balcony potted plants.
However, to my dismay, I find that over a period of time the chains
are tarnishing.
Silver tarnishes whether sterling or fine. It’s the silver reacting
with sulphur, not oxygen, which causes the tarnish - silver
sulphide.
I used a Sunshine Cloth to polish them, and the chains left huge
black marks where I drew them through the cloth---really black.
I’m sure any metal would leave black streaks on a polishing cloth,
as it is impregnated with a polishing agent, so actually takes some
metal off onto the cloth. It’s also removing the tarnish, as well as
a thin layer of fine silver.
I tested the fine silver wire by heating it with a torch. It acts
exactly like fine silver. It does not darken in the least from the
torch.
Sterling will blacken with such a test, because the copper in the
alloy is reacting with oxygen when heated, but without any copper,
the fine silver will not do so. Such a test is not a test for the
tarnish seen occurring on silver - unless I’ve got the wrong end of
the stick and have misunderstood what you were saying.
The silver stays bright, does not darken from the heat of the
torch. However, over time the finished chains are all turning
yellowish and tarnishing? What would cause this? I am really
puzzled.
Darkening from heat of a torch is caused by oxidation of the copper
in sterling alloy; obviously fine silver is not subject to this as
there is no copper present. However, fine silver is subject to
tarnishing caused by formation of silver sulfide on the surface.
Enough sulfur is present in trace amounts in room air to cause the
tarnish you observed. That is why special tarnish-proof storage bags
are often used for sterling, fine silver, and silver plated objects.
Light sulfide tarnish is yellowish, heavy tarnish is nearly black.
Use of potassium sulfide (“liver of sulfur”) is a well-known way to
achieve a controlled darkening of silver.
I apologise for my spelling of "sulphur", I'm an old dog and I
don't like the new spelling.
I’m with you on the sulphur spelling Charles! I don’t understand why
people have to change the spellings of words which have been
perfectly fine for centuries - but that’s just me, I’m old fashioned.
Everyone has an allergy to sulphur. In the form of the oxide it
makes a gas that combines with water in the nose and lungs and
causes damage. As hydrogen sulphide - the dissolved gas used to
patinate silver and copper- it smells of bad eggs, gradually
desensitizes the sense of smell and can lead to suffocation.
Used in a well ventilated area and in small quantities you are no
more likely to affected by the patinating material than by the smell
of rotting seaweed. It’s the same stuff.
And just to get this off my chest Argentium can also tarnish and
stainless steel can rust.
I would think Argentium could tarnish, hit has copper in it doesn’t
it?
Stainless, well it depends on the alloy. Rust maybe not for all, but
definitely corrosion does happen. The acid in your skin is strong
enough to screw with stainless
I'm with you on the sulphur spelling Charles! I don't understand
why people have to change the spellings of words which have been
perfectly fine for centuries - but that's just me, I'm old
fashioned.
I learned and like the ph. I use a british spell checker and I
believe that I still had to threaten this dumb machine with a large
stick to match my preferences. I guess I’m old fashioned because I
see big sticks as programing tools
Thanks to everyone who took the time to respond to my question about
fine silver tarnishing. I now understand that the problem is caused by
sulphur. I will purchase some tarnish proof storage bags to protect
the woven chains that I make from fine silver.
I would think Argentium could tarnish, hit has copper in it
doesn't it?
Copper has little to do with tarnish (it does affect the rate of
tarnish somewhat) tarnish is silver sulfide any high silver alloy
will tarnish.
Stainless, well it depends on the alloy. Rust maybe not for all,
but definitely corrosion does happen. The acid in your skin is
strong enough to screw with stainless ;-)
Stainless is just that stain less not rust proof. All stainless
alloys will rust in the right conditions but some of those
conditions are rather extreme. Chlorine compounds are typically good
at causing rust and corrosion on stainless.
