Have any of you folk tried to use NIELLO? For those who don’t have
jewelry books, this is an inlaying material which is very durable. It
is a black material consisting of an alloy of silver, copper, and
lead mixed with sulphur and heated, which would produce a mixture of
silver, copper and lead sulphides. Having made a lump of it, one has
to grind it up to a fine powder, and like enamelling, push the powder
into the depths where it is to be inlaid, heat strongly, put more in
to fill the depths completely, heat again, then abraid the job to cut
the niello down to the surface of the work. I thought I’d try making
it a while ago (outdoors!) - and finished up with a mess and an
unusable crucible. I’d made two rings which fitted neatly one instde
the other, with the outer one pierced with a sort of Roman pattern
and soldered them together. That is what the niello was for as I
tried the usual ‘liver-of-sulphur’ blackening process and after six
months the ring was returned with most of the black missing. I
finished up using a hard epoxy resin containing a black pigment.
Anyone had any success with niello?
Hello Joel;
I’ve been working with niello since 1972. Here’s a paper on it from
my old mentor, Phillip Fike. This may already exist in the Orchid
archives.
David L. Huffman
…
The Manufacture and Application of Niello
as taught by the late Phillip Fike, Master Metalsmith and Niellist.
// – Equipment and Materials: – //
…
First, prepare your ingredients and equipment.
-
12 grams of sterling silver (fine silver if you prefer), you may
use scrap silver, as long as you grind away any solder. I’ve not
tried the new “De-Ox” anti-tarnish silvers, but I suspect they are
not a good choice. -
4 grams of copper (copper plumbing works best, it’s best if the
copper is pure, a lot of sheet copper and copper wire contains other
alloys in minute amounts to aid in manufacture) -
4 grams of lead (there are other recipes, particularly in Oppi
Untracht’s Metal Techniques for Craftsmen which contain less lead
and other proportions of silver and copper and even bismuth). -
A ceramic crucible, which, henceforth, will only be useful for
making niello in. Either use one with a handle, or have some tongs
with which to pick it up. -
Borax flux. (I prefer borax either from a ceramic supply house or
chemical supplier, or from a jewelry or casting supplier, as 20 mule
team borax contains perfumes and other anti-clumping agents). -
A hardwood dowel, about 1/4" diameter and a foot long. (You can
use a carbon rod to stir with, but it better be long enough since
carbon conducts heat rather quickly and you don’t want your stir
stick getting to hot to hang on to before you’re done with it.) -
A piece of angle iron, 1-1/2" a side, about 1 & 1/2 feet long.
(You can use smaller angle iron if your aim is particularly good.) -
A 1 inch ball of damp clay (not plasticine, but pottery type
clay, any kind. You can also use furnace patch for this.) -
An oxygen/gas torch with a big tip. You’re going to have to melt
copper with it, and that takes a lot of heat. If your tip is too
small, you’ll be at it a long time, possibly driving a lot of oxides
into the metal. I like oxy/acetylene, but oxygen and propane, mapp,
or natural gas will work. Just so long as you can get a good volume
of heat into the metal. A micro torch might work if you have a
"rose-bud" tip for it. Use a neutral flame, even to some degree
carburizing.
// – Making the Niello: – //
…
-
Make sure you have excellent ventilation, either from a fume hood
with a strong fan, or work outdoors with a breeze at your back. If you
want to use a respirator, you’ll have to do the research to find one
that will be adequate. -
Set the channel iron, “V” up, on an incline of about 30 degrees.
Block off the bottom end of the channel with the clay. You are going
to pour the molten metal into the top of the channel and it will run
down, freezing into a long stick. If it gets to the end, you don’t
want it running out into a puddle. You’ll find out after the first
pour if you need to increase or decrease the angle. -
Pre-heat the crucible to a nice cherry red and flux it with a
little borax, enough to coat it nicely. You’ll probably use an old
crucible, and this is fine too. Just so long as the inside is nicely
glazed with flux. -
Melt the copper first. Copper will not flow readily, and will
tend to boil a bit at the surface, but as soon as you can see that
there are no longer any solids left and that it has consolidated into
a single mass, you can add the silver to lower the melting
temperature. You’ll need to add a bit of flux as you melt the copper. -
Add the silver and keep the mass molten until it appears that the
two metals are thoroughly mixed. Flux again if you need to (if the
surface appears not to be shiny and fluid or appears leathery). -
Add the lead, taking care from this point on not to expose
yourself to breathing in the fumes from the melt. Mix it in by gently
swirling the crucible. Don’t overheat the metal at this point, as the
melting temperature will now be considerably lower than it was before
adding the lead. Heat just enough to keep the melt liquid. -
Dump about a teaspoon of sulphur onto the melt and stir it in with
the dowel. Don’t be leaning over it at this point. The sulphur fumes
can knock you right on your rump! Keep re-introducing the torch just
enough to keep everything molten. It won’t take much heat at this
point to keep the metal molten. The dowel will burn, which is fine.
When the ash gets to long, just stump it down on a brick. If ash
falls into the melt, don’t worry, just continue to heat as it will
burn away with no effect on the niello. Continue to melt and stir the
sulphur into the metal. You will see it take on a greasy black
appearance. Take care not to overheat. Add more sulphur and continue
stirring. It will take perhaps 3 or 4 additional teaspoons of sulphur
to create the maximum amount of sulfides in the metal. You will need
to add less sulphur as you become more efficient at stirring the
sulphur down into the melt. Actually, 12 grams of sulphur can be
enough. There is no likelihood that you can use too much in all, but
you can add so much at one time that you chill your melt and have to
wait for a lot of smelly sulphur to burn away. As you try this
process, you’ll find that adding the sulphur is the least desirable
aspect of the process, hence, the less you can get away with, the
better. -
While keeping the torch on it, swirl the now complete niello melt
in the crucible to establish that it is all molten. Now pour this out
at the top of your inclined channel, and watch as it streams down and
freezes into a long stick. This stick will curl up slightly as it
cools, coming free of the angle iron. -
Break the stick into manageable pieces, anywhere from 2 to 6
inches long. If you detect a silver core in the stick, usually near
the top of the pour, it simply represents an area of metal that
didn’t get enough sulphur stirred into it. Keep only the sticks that
don’t exhibit this core, (visible from either end) and save the
silver-cored stuff to re-melt, either immediately (and add more
sulphur and re-pour) or use it when you make your next batch of
niello (but add it only after you’ve melted in the lead and just
before you begin adding sulphur to the mix.) If the Niello doesn’t
break easily, and instead, tends to be bent back and forth to break
it, you haven’t worked enough sulphur into it. If that’s the case,
simply break it up, put it back into the crucible, and re-melt it,
adding more sulphur. That’s it! You should have niello now to work
with.
// – Suitable Applications: – //
…
Niello can be inlayed into sterling silver, fine silver, karat golds
(I’m certain 14K and over, probably 10K too, and who wants to work
with anything less unless shakudo might be a candidate). It won’t
stick to steel or copper alloys, unless there’s thick coating of
silver. I’ve never tried it on platinum; let me know if you get it to
work.
It has a lower melting temperature than the commonly used silver
solders, so both fabricated and cast articles will work. It is
difficult to apply to heavy castings, since these retain heat.
Applying niello is a an art of melting and freezing, and it runs
freely, so with a heavy article, it becomes tricky to “juggle” the
stuff around on the surface without it just running right down to
find a level. It is, like lead, capable of etching it’s way into
another metal after prolonged heating. You must neveroverheat the
niello. If your finished product exhibits crystalline silver
inclusions, this is the result of overheating and precipitating the
silver out, or evaporating out the lead and the sulfides. There is no
way to correct this except to dig it out and reapply new niello. You
can cast niello into solid masses with vacuum or centrifical casting
methods, but I prefer either vacuum assist or direct pour, since the
stuff is so liquid when melted, it tends to splash out of a
centrifical crucible when the machine is released. You’ll get a rough
object which can be finished and polished. It looks amazing, like
bluish hematite, when finished.
Niello can be inlayed into engraving, etching, chased areas, amidst
cloisonne, into saw piercing (as long as it has backing), any
recess. It can be quite a shallow recess, but consider if it will be
thick enough to allow you to finish it without going through to the
metal underneath. You can apply it on flat, concave or even convex
outside surfaces, but the edge of a field of niello needs to be
protected, since it is brittle. Think in terms of enameling if that
helps. Likewise, it shouldn’t be expected to withstand flexing. You
can go all the way around a ring, or even a sphere, if you develop a
touch for it. You can drill through it, but take care, it’s that
brittle thing again. You can carve it, gently. But it’s not as
durable as it is inlayed and finished flat. You can’t expect it to
behave metallically, except in polishing, so flush setting in it
isn’t going to happen (unless you bury a stone in it while it’s
molten and then carve away to expose the stone.
// – Applying Niello: – //
…
I prefer paste flux, like the “Handy Flux” type. Self pickling
fluxes don’t cover as well, but they will work. Experiment. I thin
the paste flux down with water to a thin slurry. Pickle, rinse and
dry the article to be niello’ed. If you are going to work over curved
surfaces, you have to be able to juggle a torch, a stick of niello,
and move the work around simultaneously. I like to use a wire work
jig held in an “egg-beater” style drill (brace), which is, in turn,
held in a small bench vise. This is great for things like rings,
chalices, etc. You need to be able to juggle the melting niello
around as it freezes, catching it where you want it to stay. Flat
work is simple. Just support the piece on a brick, solder pad, etc…
(Careful! Contamination with niello is virtually the same as
contamination with lead. You get niello on a piece of gold or silver
and then do hard soldering on it, it will eat it just like lead
solder).
Flux the work, and mask off areas that you really wouldn’t want
niello on with white-out or yellow ochre. Heat the article, somewhat
more specifically where you want to apply the niello. You’ll be
working somewhat locally. If you have the whole article up to heat,
it will be harder to control the flow and solidification of the
niello. Here’s how to start: heat for a while, when the flux is
molten, take away the torch and touch the niello to the metal. If it
doesn’t melt and flow, much like touching a crayon to a hot piece of
metal, take away the niello and heat some more. Once the niello is
flowing onto the metal, you are off and running, adding niello,
backing away with the torch and letting it freeze, coming back in
and adding more. You will seldom heat the niello stick itself,
rather, you will keep the metal hot enough to keep “feeding” the
stick onto the object’s surface. You always need to overfill the area
slightly. While you are melting in the niello, you will see globs of
flux float to the top. Take your solder pick and “pick up” these
globs of flux. Underneath each glob of flux, a trail of flux flows
down into the niello to the metal below. This little “tail” of flux
will become a pit in the niello when it cools if you don’t pick it
up. Your finished application of niello should be smooth, slightly
matt in appearance, and free of all flux on it’s surface. You can
then finish it down with files and sandpaper. It will polish after
400 grit (600 grit for the purists) with Tripoli and finally rouge.
You can go back at any time and add more niello, grind out bad areas
such as pits, as long as each time, you are slightly overfilling the
area to allow you to finish back to where you want. Just remember,
the stuff will wreak havoc with your hard soldering if you get your
solder area contaminated with it, so clean files, solder pads, etc.,
before you go back to silver or gold work.
Have fun!
David L. Huffman
Joel,
Have any of you folk tried to use NIELLO?
Long ago I made a batch or two. A good exhaust system but the
resturant next door sucked air in about 6’ away 
That took some
explaining. The stuff neededs to be handled as enamel and no
soldering after application. Nasty stuff in niello so be carefull.
The results looked good but needs to be worked with extra caution. I
don’t keep any of the stuff around anymore.
jeffD
Demand Designs
Analog/Digital Modelling & Goldsmithing
http://www.gmavt.net/~jdemand
My friend play with this, I’ll forward your question.
Regards Charles A.
Hi Joel,
Niello’s definitely on most people’s “too weird to worry about”
list, but it’s neither horribly uncommon, nor all that difficult to
produce.
Phil Fike used to do workshops on it all the time, and he’s got a
solid writeup on it in the book Metals Technic.
(Details here: http://www.ganoksin.com/gnkurl/17s )
Having made at least enough of it for my own use, I have two
suggestions: (A) make sure you’re UP wind of it (outdoors) when
you add the sulfur, and (B) this is where either a full face
respirator, or a set of gas-tight goggles come in really handy. The
vapor combines with the water in your eyes (and lungs) to produce
sulfuric acid. A uniquely unpleasant experience, believe me. (I got
downwind of it exactly once when demoing it.)
(It’s not really much of problem when you’ve got decent ventilation,
I just got caught aback with it once at an outdoor demo.)
For whatever that’s worth.
Brian
PS–> It’s got lead in it, so remember to quarantine the tools you
use for it, and be fanatical about cleaning up after yourself. If
you think this is because of any health risk to you, stop and read
the article, right now. (There’s no risk to anyone in your household,
it’s your nice expensive silver that’s at risk. )
Hi Joel,
I have not tried niello, however I did study with Philip Fike and
would not recommend continuing your pursuit of it. It is a health
hazard. However if you wish to continue down this path, I would
recommend looking up whatever material you can find on Philip as he
mastered the technique. I don’t have his formula, but I do believe
there was also mercury involved.
Be safe,
Christine
www.christinebossler.com
Have any of you folk tried to use NIELLO?
Being primarily a hobbyist who is trying to emulate pre-17th century
techniques, I gave niello a shot. It took a couple of tries to get a
good result, but it works well. The problem is not technical, but
modern sensibilities. Many people, on being informed that the inlay
is a LEAD amalgam are half afraid to even handle such pieces, much
less wear them.
I chalked it up to knowing that I can use the material, but it’s
more hassle than it’s worth. For actual finished pieces, I went back
to colored resin.
Ron Charlotte – Gainesville, FL
I don't have his formula, but I do believe there was also mercury involved.
Phillips formula and methods are well described in “Metals Technic”,
edited by Tim McCreight.
As to merucry, nope. No mercury involved in Niello, niether Phillips
method, nor other traditional or ancient ones I’m aware of, though of
course for almost anything, somebody will have tried variants, so no
doubt, some fool has managed to involved mercury with the Niello
process somewhere… But it’s not needed, nor usually used.
Mercury, however, was used in fire gilding, a method of gold coating
used prior to the development of electroplating, and sometimes used
(very carefully since, as the effect is somewhat different. The
people who did fire gilding (with mercury) had a tendancy to live
rather short lives…
Knowing Phillip, he no doubt at some point may have experiemented
with fire gilding if for no other reason that to fully understand
it. But I think I can safely say that he was sane enough not to make
it a part of his normal repertoire of techniques, and it’s not
related to niello.
Niello, however, can be nasty enough without mercury, if only from
the sulphur fumes alone, not to mention melting lead. That’s one
reason Phillip generally preferred to prepare the stuff outdoors on
a day with a bit of a breeze. Once made, it is easy enough to
actually apply without generating unusual fumes, but when initially
mixing the molten metals with the mercury, it’s a sulphurous smelly
affair indeed. The lead content of niello, however, is not fixed.
Over the ages there have been many varied compositions used for
Niello, including ones made with only silver copper and sulphur,
without lead at all. That makes for a rather higher melting Niello,
and one that is more brittle and harder to burnish. But it can be
done. The lead, when used (usually), lowers the melting point, and
makes the material both more forgiving in application, and softer and
more plastic, easier to burnish to a nice finish.
Peter
4. Melt the copper first. Copper will not flow readily, and will tend to boil a bit at the surface, but as soon as you can see that there are no longer any solids left and that it has consolidated into a single mass, you can add the silver to lower the melting temperature. You'll need to add a bit of flux as you melt the copper.
Copper is very difficult to melt, so I can offer a refinement to the
described process.
Roll you copper to the limit of you mills. The thinner, the better.
Glaze copper sheets on both sides with borax. Melt you silver first,
and when silver is fluid and shiny, grab you prepared copper with
tweezes and stir your silver, while heating your crucible. You would
see that your copper dissolves in silver quite easily and without any
oxidation.
Leonid Surpin
The problem is not technical, but modern sensibilities. Many people, on being informed that the inlay is a LEAD amalgam are half afraid to even handle such pieces, much less wear them.
I think you will find that jewelry with niello is actually illegal
now. Ever since the lead content in Chinese import children’s
jewelry sent the consumer protection folks into overdrive there have
been a series of laws enacted concerning lead content in jewelry and
there is no way a niello item would pass muster. BTW lead poisoning
is nothing to scoff at I know a few folks that got it from cleaning
up an old paint factory it is bad juju.
James Binnion
James Binnion Metal Arts
Copper is very difficult to melt, so I can offer a refinement to the described process.
I’ll agree with that, copper is difficult to melt in an open
crucible, crucible furnaces make it much easier.
A JTH-7 Bernzomatic hose torch will melt it in a micro-furnace. You
need to contain the heat to melt the copper. Copper and gold melt
very easily in that environment.
Regards Charles A.
We made neillo as part of a workshop I took with Mary Ann Sherr,
some time ago. I never had occasion to make it again, though. It was
a wicked nasty process, that HAD to be done outdoors, with a breeze
at your back, and caution about others being down wind.
I still have a small supply of the product in my bag of tricks, that
comes in handy when someone needs repairs on an old neillo piece. As
Mr Rowe said, once you have made the mixture it is not a messy, or
particularly hazardous material to use.
I’ve made it with varying results… and the hassle of making it and
keep ing the tools separate detracts from really using it on a
regular basis. I would mention that you can purchase pre-made niello
from a company in the UK, I just can’t remember off the top of my
head who the vendor is. Perhaps some of our UK friends can help. It
is quite expensive as I remember. It is a pain to make if you are
going to use it much, but that would give you control over the
formula. Oppi has several different formulae in his book “big” book.
Metals Technique has a nice section on Niello. A fan really helps
when you make it. If you are not making it outside you need a really
good vent hood going. You still need the fan outside… or a good
wind to your back. You only need one good nose hit of the fumes to
pay attention to it next time 
I have been meaning to play with
underfired black enamel to try to get the same effect.
Have fun and be careful!
Dear David greatly appriciate your posting of the Phillip Fike
recipee, thank you, i was close to ordering the book suggested on
his Niello work. i hadd been curious about the workings of it since
college but was all discouraged by the teachers in charge when ever
I came to making up a batch, so it always got shelved and moved away
from, I wonder if there was an alternate to lead? thanks again david
Hratch
Atelier Hratch Babikian
We made neillo as part of a workshop I took with Mary Ann Sherr, some time ago. I never had occasion to make it again, though. It was a wicked nasty process, that HAD to be done outdoors, with a breeze at your back, and caution about others being down wind.
Whenever one has to do some process, by-product of which some nasty
gas, remember charcoal. A lot of cover flux recipes contain powdered
charcoal, which function is to absorb gases out of the melt. Cutting
a lid out of charcoal and letting it float on the surface of the
melt, is also a good solution.
Leonid Surpin
i hadd been curious about the workings of it since college but was all discouraged by the teachers in charge when ever I came to making up a batch, so it always got shelved and moved away from, I wonder if there was an alternate to lead?
Lead in niello is not the first fiddle and not even the second. One
can do niello with copper, silver, and sulphur alone. Lead is added
to lower the melting point and to make alloy cheaper. Tin can be
substituted instead of lead. Think of niello as alloy of silver and
sulphur.
Other components are added to make it suitable to a particular
project.
Leonid Surpin
I think you will find that jewelry with niello is actually illegal now. Ever since the lead content in Chinese import children's jewelry sent the consumer protection folks into overdrive there have been a series of laws enacted concerning lead content in jewelry and there is no way a niello item would pass muster. BTW lead poisoning is nothing to scoff at I know a few folks that got it from cleaning up an old paint factory it is bad juju.
The pieces I was working with were belt mounts, not skin contact
jewelry. In any case, I wrote it off as more hassle than it’s worth.
Even with the exhaust hood, I was wearing a respirator mask. In
Florida weather, on top of torch heat blowback, it was right
uncomfortable (and I like it warm…).
In California, yes, such pieces are specifically illegal, and there
may be other states that are moving that way. Federally, the
regulations apply to childrens’ products.
Ron Charlotte – Gainesville, FL
Hi Leonid,
Whenever one has to do some process, by-product of which some nasty gas, remember charcoal. A lot of cover flux recipes contain powdered charcoal, which function is to absorb gases out of the melt. Cutting a lid out of charcoal and letting it float on the surface of the melt, is also a good solution.
Have you ever made niello? We’re talking vast quantities of flaming
sulphur, and then stirring the burning sulphur into the mix with a
(long) rod. No way to float charcoal on it. (The sulphur is already
floating on it, and the goal of the stirring is to mix it in.) (Now
that I think of it, you’re essentially covering the melt with sulphur
just as you would cover a normal melt with charcoal. The difference
is that then you mix it in. Niello’s basically a metallic sulphide,
so the goal is to get as much sulphur into it as you can, any way you
can.)
On the other hand, burning sulphur definitely looks neat: picture
blue flames with black edges. Looks like something out of a bad
horror movie. (and if you get downwind of it, it is something out
of a horror movie.)
Regards,
Brian
Tin can be substituted instead of lead. Think of niello as alloy of silver and sulphur.
Hmmm, hadn’t thought of substituting tin for the lead. I think I will
have to try a small batch to see how it works.
Ron Charlotte – Gainesville, FL
The vapor combines with the water in your eyes (and lungs) to produce sulfuric acid.
Not to dump on Brian, but no, it doesn’t. It forms sulfur -OUS acid,
which is a weak acid.
SO2 + H2O → H2SO3, sulfurous acid. SO3 +H2O → H2SO4,
sulfuric acid. Sulfur burning or combining in ozone will do it, which
is one form of acid rain.
That’s just in the interest of accuracy. Sulfur dioxide is quite
poisonous in itself, and inhaling it creates acid, too. It’s still
nasty.
And from Brian’s post and also Jim’s. I had a friend who had been a
union painter at a shipyard starting in the 40’s. He was on
disability from the lead paint. He was a real mess, and it was
permanent. Couldn’t remember what he had just said, couldn’t keep
his hands from shaking… People hold lead in their hands all the
time without problems, but anything that gets it into your body
chemistry is to be avoided at all costs. The hazards are NOT
overstated, in this case. Me, I’d inlay it with blackjade, it’s
better anyway.