My client wants an engagement ring with black everything. That is
black diamond and shank. Since it is to be worn daily for many years
it should be stable, durable and sizable. I would love to hear that
there is a black alloy for gold being a goldsmith. Ideas and
solutions please.
Thanks, Bruce in West Vancouver,B.C.
www.brucewilsondesign.com
Since it is to be worn daily for many years it should be stable, durable and sizable. I would love to hear that there is a black alloy for gold being a goldsmith. Ideas and solutions please.
If you could figure out how to do this you could easily retire from
the proceeds of the invention. There are exactly three colors of bulk
metal: red (copper) yellow (gold) white/grey everything else. Any
other color you see on a metal is some form of coating whether it is
an oxide or other chemical compound (patina). Coatings don’t last on
rings, how long they last varies but they all wear off eventually. I
have seen a black coating that is done by a very high tech vapor
deposition process that is very durable, probably the best I have
seen but even it will wear off eventually.
James Binnion
James Binnion Metal Arts
Hello, to my knowledge “Black gold” is a surface treatment. The
simplest being “Red Gold” treated with Potassium Sulphide to oxidise
the copper content of the alloy. Gold can be plated with Black
Rhodium or Ruthenium and I believe there is a laser treatment which
affects the light absorption of the the gold making it appear black.
All of these are surface finishes which will need refinishing from
time to time. The Victorians used to enamel the gold with vitreous
enamel fired into recesses carved out of the gold. The technique is
called “Champleve” where the metal is gouged out or etched out to
accommodate the enamel which is then fired in to place.
It will be interesting to see what other suggestions people come up
with!
Hamish
Stuller sells black ceramic rings in half sizes.
Ive had these clients too!!
they want the impossible.
There may be such an alloy but ive never heard of it. What the client
wants is a contradiction in terms. You could do him/her a normal gold
band with black enamel inlay. However enamel on rings is also a non
starter. Like black dyed anodised aliminiun.
Or heavily fired titanium. This comes out a nasty dark gray colour.
You could do a comlete circle of table black diamonds around the
circumference of the band, with a BIG on in one place just to show
its a solitaire engagement ring.
How grotesque!!. But they might just love it. Charge the earth of
course.
Ted
Dorset
UK.
Cobalt steel can be oxidized. Although the most dramatic satin black
finishes are visible on the Japanese Tsuba (sword guards) which were
fabricated in pig Iron (low carbon). Their patina formulas were a
trade secret but there’s plenty of research to be found in the public
sphere. Then too there are gun ‘blueing’ and blackening patinas. As
James stated, they’re all coatings that will wear off with use. That
may be your challenge, designer, to come up with a protective sheath
around a sensitive blackened center.
Good luck.
Kim
I have seen a black coating that is done by a very high tech vapor deposition process that is very durable, probably the best I have seen but even it will wear off eventually.
Do you know anything about that laser process, it leaves a texture
on the surface of the gold that doesn’t reflect light (apparently),
so it’s dead black ? CIA
We had an Excellent Jeweller in Australia called Ron Keogles
(Spelling?) He made beautiful jewellery in Niobium which he blackened
by some difficult industrial process, before blackening he set
diamonds directly into the grey niobium surface. He often incorporated
18ct gold and diamonds. I never met him but I held him in high
regard, he retired some years ago. I believe the black was very hard.
There have been several posts on Niobium over the years pointing out
the dangers of working in niobium. It is much softer than Titanium
and I believe about the same price as 14ct gold, I am probably wrong
there.
David Cruickshank
jewellerydavidcruickshank.com.au
It will be interesting to see what other suggestions people come up with!
Sometimes we taking things too literary. Clients simply state their
desires. It is our job to interpret these desires within the range
of what is possible. We cannot produce black alloy, but we can cover
the surface with black diamonds pave style. The appearance will be
even more interesting that simply black metal.
Leonid Surpin
I’m interested in hearing about black alloys as well. We’ve done a
lot of playing with black coatings: liver of sulfur, black rhodium,
black nickel. Everything wears off, some more quickly than others
and mostly it depends on the wearer.
Amery Carriere Designs
http://amery-notesfromthefuture.blogspot.com/
I believe there is a purple gold patented by a Swiss company I have
heard it contains aluminium and is very breakable and is only
suitable for casting. May be wrong? There was an article about it in
the Goldsmiths Hall technical publication some years ago.
David Cruickshank (Australia)
jewellerydavidcruickshank.com.au
I have read the description, since it is a surface modification by
the laser it will be as soft as the base gold and will be very
fragile. So I doubt it will find any use in jewelry.
James Binnion
James Binnion Metal Arts
I'm interested in hearing about black alloys as well
I will repeat agin there are no black alloys, none, no way, no how.
All “black” metal items are coated in some form or fashion.
James Binnion
James Binnion Metal Arts
Yes there are purple, blue and green gold intermetallics. I don’t
really consider them to be metals as their crystal structure makes
them rigid and brittle like glass and they also easily corrode in
normal environments. They are laboratory curiosities and not
something to make jewelry from. By the time you add enough alloying
elements to them to fix the brittleness and corrosion issues they
are no longer very pretty. There have been some attempts but they
have not worked in the market place due to these issues.
James Binnion
@James_Binnion
James Binnion Metal Arts
360-756-6550
I believe there is a purple gold patented by a Swiss company I have heard it contains aluminium and is very breakable and is only suitable for casting. May be wrong? There was an article about it in the Goldsmiths Hall technical publication some years ago.
Some swiss company may have trademarked their version, or even
patented a method of preparation or use, or some such, but they
hardly developed the stuff. Purple gold has been known for a long
time. One instance in particular has been well documented is the
formation of these compounds in electrical connections when gold
plated connectors are in contact with aluminum parts. In that
instance, this can form, essentially like a corrosion product, to the
detriment of the electrical connection.
For jewelry, the problem is that these “alloys” (there are several
ratios of gold and aluminum that form these compounds), of gold and
aluminum, are not true alloys with the typical structure of a gold
alloy. They are called “intermetallics”, and have a completely
different crystal structure from usual gold alloys. They behave more
like a ceramic or glass. You can cast it, but it must be cast in a
completely oxygen free environment, and isn’t easy to either prepare,
or cast. It can also be shaped/machined in the same way any lapidary
material can be shaped, via grinding or machining with suitable
tools (usually diamond tools). A number of jewelers have played with
the stuff over the years. One well known one was the late Steven
Kretchmer, who explored the stuff in the 80s and 90s, I think,
soldering chunks of the stuff to his jewelry (an advantage over stone
is that you can solder it to things, not just set it like a stone)
Another fellow I recall reading of in the 70s, used the material by
doing raised or spun hollow ware in aluminum, gold plating it, then
heating it just until the gold formed an intermetallic with the
underlying aluminum, giving him a durable bright purple metallic
finish. Kind of a cool use. It was in a little short book he wrote,
but I have no idea where my old copy has gotten to…
Peter
This is an interesting thread. Now I’ve been reading the books that
other people had sent me, and I understand there is a mixture known
as “niello”, being composed of silver, lead, and sulfur, that is used
in contrast with metals in jewelry.
Of course, lead is far too toxic to use casually these days, which is
why I suppose we don’t see niello in current jewelry…
Andrew Jonathan Fine
I have read the description, since it is a surface modification by the laser it will be as soft as the base gold and will be very fragile. So I doubt it will find any use in jewelry.
I was thinking that zapping a recessed part of the jewellery may
protect the black?
I don’t think it’s a shiny black, but there are applications where a
dead black colour may come in handy, sort of a marriage between
jewellery and computer vision.
Regards Charles A.
I think Jim Dawes made some blue gold as an experiment, using an
aluminium can and some gold. If memory serves he may have said the
surface was like a a patina.
Regards Charles A.
“Black gold” is not just an expression anymore. Scientists at the
University of Rochester have created a way to change the properties
of almost any metal to render it, literally, black…:-)…!
SEE: Ultra-Intense Laser Blast Creates True ‘Black Metal’
http://www.ganoksin.com/gnkurl/1q0
Janet in Jerusalem
This is an interesting thread. Now I've been reading the books that other people had sent me, and I understand there is a mixture known as "niello", being composed of silver, lead, and sulfur, that is used in contrast with metals in jewelry.
Usually it also has copper, and some formulations don’t have the
lead. Niello has a long and rich history, and is still used widely in
some other parts of the world. But it’s application doesn’t lend
itself as well to commercial mass production, so you don’t see it as
much in the “west”. But you can find various artists, some here on
Orchid, who’ll use the stuff now and then. I’ve used it myself now
and then when it seemed the right material for a given design. At
one time, it was very frequently used in some Asian work, especially
Thai and Indian work. Less so today, mostly because it’s more work
and more cost than resins, paint, or enamels. But you can still find
it’s use easily enough if you look around in that part of the world.
Here in the U.S., the late Phillip Fike, who taught at Wayne State
University in Detroit for decades, championed the rediscovery and
exploration of Niello among American craftspeople, and though he’s
passed on now, many of his former students still use the stuff. You
can find a fine write up of the process in “Metals Technic”, edited
by Tim McCreight, as well as in Oppi Untracht’s two books, and a
number of other references.
Of course, lead is far too toxic to use casually these days, which is why I suppose we don't see niello in current jewelry...
All the metals, silver, copper, and lead, in Niello, are converted
to a mix of metal sulphides (just as the tarnish on sterling silver
is black silver and copper sulphide). It doesn’t have the same
toxicity issues as metallic lead does, at least not in finished
jewelry (though I wouldn’t suggest sucking on the stuff like candy,
and it’s not a good choice for children’s jewelry or for application
to surfaces that are in direct continuous contact with skin like the
inside surfaces of a ring shank…) The main toxicity issues are in
the initial preparation of the stuff. messy, smelly fumes, it needs
to be done outside in a decent breeze. Once made, it’s easy enough to
apply without toxicity problems, so long as you don’t grossly
overheat it… In use, it shares many of the uses and visual
characteristics of black enamel, with subtle differences, and it
remains slightly plastic, like a softer metal (part of the
application process is burnishing, just as might be done to metal),
so it’s durability is quite different from hard but brittle enamels.
Peter Rowe