I use liver all the time on my silver pieces, so will try to take a
shot at helping.
- Temperature matters.
I tend to use the liver warm (not hot, never boiling) and the piece
at room temp to slow down the process, because I aim for intermediate
colors -- the golds, reds, blues and purples -- rather than black.
When the color I'm looking for is reached, I quickly dunk the piece
in COLD water (or run it under cold water) to stop the action.
If you want to go for black (then polish off the high points), you
can warm the liver and also warm the piece of silver (for example,
have a pot of hot water that you can dunk the silver in to bring it
up in temp before dunking it in the liver.
You can also use the liver solution cold, which slows down the
process even more.
- Strength matters.
The solution can be mixed at various strengths, which will yield
different results. Even when going for intermediate colors, I mix
the liver at "normal" strength; however, if I needed extra-fine
control I might mix it a little lighter.
Going TOO strong is just going to make everything really black,
really quickly, with no opportunity for control.
- How you apply it matters.
If I were simply going to blacken all the recesses of a piece, I
would dunk the entire piece in the liver, let it blacken, then polish
the piece with a firm buff (which will polish all the high points,
leaving the recesses untouched). You can also use very fine (000 or
0000) steel wool to polish the high areas, depending on the surface
However, I frequently use a fine pipette or tiny paintbrush to apply
the liver solution to a piece, which affords me much more control
over the application of the patina. Again, it's my style of
patination that dictates this choice.
- You can vary the results chemically.
Liver can be mixed with ammonia and/or salt to yield different
results in color and texture, including wonderful iridescents.
Experimenting with it is the best way to figure out what works for
your style and will produce what you want.
For example, I've gotten wonderful results by applying "regular"
liver to the piece and then at specific points in the process (with
the liver still in place), spraying the piece with diluted ammonia;
or sprinkling salt granules onto the mix. It's a process of trial
and error that you just have to watch and play with until you get the
results you want.
- If at first you don't succeed...
Try, try again. You can always burn off the patina by hitting it
with a torch, then reapplying it. This can be a great way to
practice getting different results on the same piece. Sometimes,
it's also necessary if you realize you've gone "past" a point that
you really liked.
- Take note the first several times you do it.
The colors will appear in the same order each time -- basically,
gold --> red --> blue --> purple --> black. Note the way that the
colors form and roughly at what point in the process each "develops."
Also note what happens if you add mixtures (ammonia or salt) at
different points in the developing. By taking notes (and it's great
if you can take pictures to accompany the notes so you can see what
the result was), you can repeat things that you like on subsequent
pieces, even if you haven't used that particular effect in a while.
Hope this helps!
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