Mokume patina

Jewelry Discussion
1

Hello everyone,

I am trying to patina copper and silver mokume gane in an
ammonia/salt solution. It’s true that it’s a good patina for shakudo
(I got Steve Midgett’s Mokume Gane - A Comprehensive Study and gost
the recipe from there, I’m raving about the book, btw) but I was
hoping it would color the copper, too.

Problem is the recipe said household ammonia and I found no such
thing so I went to the Chemistry Institute and got some 25% technical
ammonia.

Can anyone please tell me what the concentration is in household
ammonia and weather I should dilute the stuff I have? And dilute with
what?

Also, if someone has tried this patina on copper/fine silver mokume
I would appreciate any tips.

Thanks a million,
Dana

2

Hi Dana,

Ammonia is a toxic gas of chemical composition NH3. "Household"
ammonia is not in the form of the gas but is actually ammonium
hydroxide of chemical composition NH4OH. The gas is dissolved in
water. The ammonia molecules each bond with one hydrogen atom from
the water molecules, producing lots of positive Ammonium (NH4+) ions
and lots of negative Hydroxide (OH-) ions. Household ammonium
hydroxide is typically 10% ammonia by weight.

If you wanted to change your 25% “technical” ammonium hydroxide to
10% ammonium hydroxide as in the household ammonia concentration,
you would add more water using the following formula:

Original concentration X Original volume = New concentration X New
volume

where the new volume is the unknown in the equation.

For example, if you started with 100 ml of 25% ammonium hydroxide,
and wanted to get to 10%, you substitute the numbers to find out how
much water to add, thus:

0.25 X 100 = 0.10 X ?
? = 0.25 X 100 / 0.10
? = 25 / 0.10
? = 250 ml

Therefore you would need to add an extra 150 ml of water, making the
volume up to 250 ml to achieve a concentration of 10% ammonium
hydroxide.

I hope this helps.

Helen Hill
Preston, UK

3

Ammonia is sold in the cleaning aisle of nearly every American
grocery store. It should be easy to find. Also, at small hardware
stores such as Ace and True Value.

Elaine
Metalsmith since 1990
and Certified PMC Instructor
http://www.CreativeTextureTools.com ™

1 Like
4

When I do this I use the patina technique posted on Orchid by David
Huffman and originated by Charles Lewton-Brian

see

It works very well for me.

Debby

5

I use houeshold amonia and it works fine on copper to put a blue
green patina on the surface.

I coat the copper with salt, (I lick it and then dip it…), then put
an ounce of household amonia in a shot glass. Put both the shot
glass and the copper in a sandwich baggie, seal it, wait 24 hours,
and you will have blue patina on the copper. I then use 4000 grit
polish paper to thin out the patina.

Love and God Bless
randy

6

Try Reactive Metal studios. You should be able to order this.

Jonheric

7

Thanks for the help :slight_smile:

Amazingly, in Europe, Romania, where I live, there is no ammonia in
grocery stores, so I’ll use Hellen’s info and transform the one I
have into a less concentrated solution. And, Debra, that technique
sounds better than what I have so I’ll definitelly try it.

Thanx again,
Dana

8

Dana, please send me too the details about the patina. I am from
Romania too and I missed the thread about it. By the way, I am from
Bacau - 0727136577

Adrian Mocanu

9

Hi Dana,

I’m glad I could be of help. The simple formula:

Original Concentration X Original Volume = New Concentration x New
Volume

is a very useful formula that will allow you to achieve any
concentration from a known original concentration, as long as you
use the correct solvent (water in the case of ammonia solution) to
dilute the original solution.

Helen
Preston, UK

10

Adrian,

I only asked how O can dilute the 25% ammonia I got to achieve the
concentration of “household ammonia” which I can’t find anywhere
near where I live. Got a very useful formula for diluting pretty much
everything (providing I also use the corect solvent :): orig
concentrationXoriginal volume=new concentrationXnew volume. And some
info on, basically, fuming the mokume piece I have in a seald
bag/container…

Here is the link from Debra:

Patina on copper - Jewelry Discussion - Ganoksin Orchid Jewelry Forum Community for Jewelers and Metalsmiths And the
info from Randy - pretty much the same thing, except for the licking
part…

Hope it helps u too.

R u making mokume?

Thanx everyone for the advice :slight_smile:

Dana

11 
R u making mokume?

Nope, I am still at the beginning (small soldering on broken chains
and small repairs) but I have been always interested in the technical
aspects and especially in the gold refining field. R u from
Bucharest?

Adrian