Household chemicals for patination

Hi out there in Orchid land. I am going to be teaching some
workshops in the near future and am in the middle of doing my
research to make the lesson plans and make examples. I have been
experimenting with many different chemicals but was wondeing if
anyone had some clever suggestions for patinas on copper, bronze,
brass and silver. I have the Richard Huges book but I was just
looking for some personal experience on some of your favorites. I
would be most appreciative!!! Thanks, T*

One of my favorite patinas is blue on brass. Put a little ammonia in
the bottom of a plastic container and suspend the brass piece inside,
cover and wait until the patina develops. You can also add a little
table salt for a slightly different effect. - Deb

my favorite is the old salt and ammonia solution…put into Fresh
Step kitty litter, with the pieces buried. It has to be Fresh Step,
with it’s magic blue crystals. You can get the most amazing blue and
turquoise colors in about 24 hours.

Wow! sounds great! How stable are the colors? And how resistant to
rubbing off? margaret

Hi…what metal are you turning blue with the kitty litter, salt
and ammonia? Does it work on different metals? Sounds interesting!
Thanks in advance…

Question : Is the kitty litter dry when you bury your pieces for
patination? Do you add any liquid ? I somehow can’t reconcile
myself to the idea that the cats themselves are going to be heavy contributors to the process.
Dee

In regards to the solution for platinum- can you explain more Thanks
Jackie Atlanta,Ga

    what metal are you turning blue with the kitty litter, salt and
ammonia? 

copper and brass

Question : Is the kitty litter dry when you bury your pieces for
patination?  Do you  add any liquid  ?  I somehow can't reconcile
myself to the idea  that the cats themselves are going to be heavy contributors to the process.

It’s clean kitty litter (used kitty litter? I don’t think so! Why do
people always ask that?) and I add ammonia (and salt of course), so
it’s not dry.

Dee… couldn’t help chipping in here, about the cat’s contribution.
So, what’s wrong with urine? There is a long history of using urine
in treating metals (also used for a lot of other things I shall not
discuss at present). Urine contains ammonia. Historically, urine has
been an accessible resource for ammonia. (Although I don’t want to
hurt feline feelings, I’ve heard that horse urine is the best.) The
liquid added to the fresh kitty litter is bottled household ammonia. Don’t we have it easy?

Get used to the idea! It’s the urine, not the litter itself, that
does all the good. In fact, it’s not actually the urine either that
causes the patination, but the ammonia that results from the bacterial
decomposition of the urine. Urine is loaded with, you guessed it,
UREA. Bacteria find this stuff positively irresistible. When they
devour it, they in turn produce ammonia. Ammonia reacts with copper in
the presence of air to produce a variety of patinas. Some soulless
folks cut out all the intermediate stuff and just add household
ammonia to litter, newspaper, sawdust etc., and get about the same
results. Hope I haven’t destroyed the Magic. Use whichever is the most fun…Bob Williams

    Get used to the idea! It's the urine, not the litter itself,
that does all the good. 

can’t do it without the ammonia, that’s true. But Fresh step kitty
litter has some sort of blue crystals which also interact with the
metal to give it that fabulous patina, so in this case, the litter is
important.

As a follow-up, my Dover edition of Theophilus "On Divers Arts"
lists nine references to using urine in its index.

I remember reading elsewhere that enamelists used to wash their
pieces of copper in urine prior to enameling.

And this raises a question. What is the reason that enamalists basify
the copper surface prior to enameling? Any one know. (Usually spit is
used, not only being slightly basic but also sticky , and as a
thought if you want to make the spit really basic, eat some bread
first).

Urine contains ammonia.

G’day; Sorry to have to contradict; fresh urine does NOT contain
ammonia. It does, however contain a number of substances that contain
nitrogen. When acted upon by certain bacteria, these nitrogenous
compounds are broken down to produce ammonia and what are called
amines, among other things, and it is the ammonia and amines that
give stale urine it’s characteristic unpleasant smell. Fresh urine is
completely sterile, by the way. But bacteria love it.

Don’t you just love it when silly old know-it-alls rush in to
contradict and split hairs? Cheers! –

John Burgess; @John_Burgess2 of Mapua Nelson NZ

Hello there, I know,it doesn’t sound tasty but did you know that
humane urine was used in the world war for neutralizing tear
gas.Soldiers urinated on a towel and breated trough it while they
closed theire eyes to protect them from the gas.But still,urine from
cats and horses could contain some little small devils who could
cause us some serious trouble if we infected ourself with them.Some
people drink theire own urine for medical reason-which I wouldn’t do-
but it’s a fact.Anyway, I think I better stop before people start
having bad ideas about me.We live in a free world so … find out
by yourself.By the way ,regular tabacco mixed with vinegar in a
plastic bag,gives some beautiful patinas on copper and brass. Regards
Pedro Palonso@t-online.de

   I remember reading elsewhere that enamelists used to wash their
pieces of copper in urine prior to enameling. 

Where did you read that? That’s the first time I have ever heard that
one! I’ve been enameling for 26 years and have never heard that. We
clean it with vinegar and salt, sparex, or nitric acid and then if
necessary, put on some klyrfire to make it stick.

   What is the reason that enamalists basify the copper surface
prior to enameling?  Any one know. (Usually spit is used, not only
being slightly basic but also sticky 

The only time I have used spit is on a piece of fine silver with waste
enamel to rub the surface so it adheres better. You then wash it off.
Louise @lgillin1

But still,urine from cats and horses could contain some little small
devils who could cause us some serious trouble if we infected
ourself with them. 

Just FYI, barring a urinary tract infection, urine is sterile.

Wo!.. am I tired… chasing that horse around the pasture was some
trip… but the exercise was good… anyone know how to get a horse to
stand still, do his thing while holding bowl or pail underneath with a
copper medallion in it for 24 hours…the chase was enough for me!!

So what is a good spray-on patina for large items mounted on a
wall… heard something to do with Tide soap and ammonia?? Jim C

Jim, Feed that horse some Bucha leaves… a diuretic used before a
race - and he will stand still and produce enough for you to patina
several life sized bronze statues :slight_smile: Brian

If you are serious about getting horse urine I can add this: I knew
a farmer who collected the stuff commercially. He had leather
buckets that had a leather strap that would go over the horse’s back.
He then positioned the bucket in the proper place . He then
colected the stuff at his leisure… Good Luck and don’t step in anything…Don