Question about coloured gold's

As a new member to the forum I have been going through some of
the older threads and have found many very interesting
discussions and comments. I am particularly interested in the
coloured gold formulas. I would appreciate it if someone could
give me some idea of the workability (fabrication, cutting,
polishing, etc., or can certain alloys be used only for casting)
of some of the various alloys. Especially the more exotic ones
— deep green, blue, black, purple, bright red, etc… Also, do
I need to use some sort of mixing agent with alloys using for
example aluminium (or would aluminium need to be alloyed in a
vacuum). Finally, are there any health concerns with any of the
alloys besides cadmium. Thanks in advance. B Goodman Van.
BC

Hello BC;

You’ve got some question,I tell ye !! I’m sure that you can find
lots of answers in the orchid archives.However here is a brief
description of the alloys I know about and howmuch. Green gold
alloy’s are made of gold and silver which is the green coloring
(discoloring)agents for the gold.In addition some copper is used
to it in order to inhance the color and to harden the alloy.Some
recipes descripe the green alloy with small amounts of
cadmium.Working with this alloy is not hard since the metal is
very plyable and easy to work with but still a kind of soft. Blue
gold can be made by using pure iron in your alloy.This alloy is
extremely brittle and not malable at all !!This alloy is not
often used by goldsmiths (if at all ?).I haven’t seen much
recipes for blue gold and I’m not looking into fabricating
some.If you ever had the experience of working with natural gold
without passing the refining process … then you know how
hard it is to deal with it. Ironsulfides in the gold are causing
it !! Black gold does not exist.It’s a surface treatment of the
gold with chemicals or with a torch (called firescale). Purple
gold is made by using aluminum as coloring agent.Same properties
as blue gold.Very brittle and you have to deal with the
aluminumoxide which make the fabrication more difficult.
Allthough,little pieces of aluminum are used in alloy’s to
inhance the alloy. Red gold has a high contents of copper.Silver
is added to make it more plyable and malable since the alloy
becomes hard when you work with it.Do not overhead the metal and
add the copper to melt as last.Use plenty of borax when melting
the alloy and do not use an oxidizing flame. White gold can be
made with nickel or platinum.Some people are allergic for nickel
but this is the cheapest way of making white gold. I know that
Rio Grande offers mixing alloys for producing your own white
gold and this stuff is real good.So don’t start using quarter
coins (almost pure nickel) to mix it with gold it will not work
thatway!!The mix with platinum needs special equipment since
platinum becomes very brittle when headed in conjunction with
iron,steel or silicium (crucibles !!)due to the contamination.If
you need to soften the metal made with nickel,never quench it in
pickle or whatever.Let it cool off on air or lay it on a cold
metal plate. Yellow gold is the most knowen alloy.It’s an alloy
of gold,silver, copper and anti oxidizers.Very malable and it’s
lovely to work with. Still concider the fact of overheading due
to the contents of copper.

This is really a short description of the commonly knowen gold
alloy’s for casting procedures.I can not give you all the
specification in one e-mail and therefor you should start
thinking of buying a book for making your alloy’s.But believe me
if I say that premade alloy’s -as the one I mentioned from Rio
Grande or other goldsmith suplliers- are the best starting point
for making gold alloy’s.I’ve don’t it the hardway and I learned
tremendous out of my expereince but I made lots of mistakes and
had to do a lot of troubleshooting.

Basicly,coniceder all fumes of metal as harmful.Cadium is very
nasty but you have to take your precautions with all of them and
never bend your face over the melting pot or crucible.Allways
stand besite of it with your head at approximately the same
hight as the melting device and use a well ventilated room.Buy a
good pair of handgloves and Eye goggles and use good equipment
which doesn’t mean that it has to be expencive.

Feel free to work with alloy’s but listen towhat other
goldsmiths you’re going to tell.I’m just one of them and other
peolpe have even more experience and knowledge then I do.

Regards Pedro
Palonso@t-online.de

Hi BC, I would suggest that you might take any blue gold recipes
with a grain of salt. There are blue surface treatments which are
secret and patented (Aurum in 1988 published an article about a
German manufacturer who had developed such a surface finish). I
have accurately followed a number of recipes for so-called “blue
gold” using iron only to discover that I had a rather indifferent
grey-white gold. I’d love to meet someone who has succeeded and
have them actually demonstrate the creation of this alleged
alloy. None of my efforts, no matter how I stretched my
imagination, came anywhere near any sort of blue - with the
exception of my language when I saw the results. Hoping for
true-blue enlightenment in post Olympic Down Under, Rex

Thanks to Pedro for his detailed re the workability
of coloured gold’s. Does any one have any experience casting
there “brittle” alloys. I had heard that some alloys were
difficult if not impossible to work with but I was wondering if
they could be mixed and cast, or mixed, allowed to cool,
remelted, and cast. As for the black gold Ricky Low posted the
following formula May 7, 1998

Black, 14k=Pure-58.3%;iron-41.7%

For those interested in such things Rick provides formulas for a
very wide range of colours. You might want to check out his
posting in the Meta Archives. As for the “oxide” problems with
some alloys, I notice a posting in regard to firescale that
mentioned stainless steel bags and carbon as a means to
eliminate (or possibly reduce) oxidation. This may reduce the
workability problem of some alloys. Other suggestions that were
made in the same thread were, pump argon into the kiln (I think
that it was argon, check before you try it), heat/melt in a
vacuum.

Further to the black gold, I had heard some time ago that
Cartier was working on a commercial black gold. Sounds wild, but
then so does many of the colours that Ricky low mentions —
i.e. bright red, gray, bright purple, brown, orange, very deep
pink, wow, what more can I say.

B G

Rex,

Many years ago, I also attempted to make colored golds, with limited
success. The blue gold that you describe looked exactly like the
gold that I got by adding iron to gold. But after I polished the
gray metal, I heated it slightly and got a beautiful blue. Just like
heating iron…wow. I decided that I could simply use iron in the
future, and save my gold for better uses.

Good luck,
Doug Zaruba