Working with Liver of Sulpher can be tricky, especially if you are
looking for absolute consistency. One of the biggest reasons is that
it is an oxide: it rides on top of the metal after shaking hands with
air and a mixture of water and sulpherated potash. This fickle little
oxide will react to anything and everything its wayward little eyes
set upon. There are a number of substitutes out theRe: some only
slightly toxic to some that are outright deadly. I have used it for
years with absolute confidence and consistency and here are the
tricks I have learned along the way.
I have one major warning about Liver of Sulpher before I get
started. If it is mixed (accidentally or otherwise)with acids it has
the potential to release hydrogen sulfide. Hydrogen sulfide is
nothing to be trifled with. Long ago, a cohort left a table in the
patina area covered in Barkeepers Friend(oxalic acid), and not
knowing what I know now, I proceded to patina a copper range hood
with liver of sulpher. The amount of hydrogen sulphide that was
released dropped me to my knees, and had I been alone in the shop, I
wouldn't be sharing with you today. That being said, a good amount
of common sense goes along way in your patina area. Clean, Clean,
Clean and a giant fan blowing the fumes away from you.
Liver of Sulpher (LoS) bag o' tricks.
- The first rule of metalsmithing is clean, clean, clean.
- The second rule of metalsmithing is clean, clean, clean.
Get some latex or similar gloves when oxidizing. They keep finger
oil off the metal, and that nasty chemical away from your blood.
I only use distilled, filtered water. The purity of the water you
are using makes a HUGE difference when it comes to this fickle little
oxide. A gallon of distilled water is cheap at the grocers. Eliminate
any unknown bits in the water and you have just shifted into high
gear smooth as silk.
I use pyrex to patina in, and immediately clean it afterwards.
Again, getting rid of anything that can court a different reaction.
Read the recipe, and scale it back by 15% on the chemical side, make
a note in your patina notebook as to the exact mixture...and note the
outcome. I sacrifice a little time to get the same result every time.
If your metal looks dry or chalky, chances are high you are mixing it
way too strong, and way too hot. That oxide will bloom under what
ever finish you seal it with and cause you all kinds of grief.
I do mine in successive, incremental layers and slowly build the
color. Now heres the trick. Lightly brass brush that naughty oxide
back onto the surface, much like depletion guilding. I have found
that just by lightly burnishing the surface, my LoS patinas are
predictable, more stable and more exploitable. It also prepares that
metal for wax to seal it.
Birchwood & Casey make an acid patina (think pH kinda like sparex)
that makes the same family of colors and is not an oxide; its
reaction is completely different and so are its handling issues. they
also make a gel form of the same stuff. Its great for monumental
finish work - you can shoot it just like auto paint and it doesnt
I had the pleasure of working with Ron Young a number of years ago,
and his solvent dyes are far out to play with as well. Just google
his name and "patina".
Just my two lincolns worth. Hope it helps.