Pickle for bronze

Pat_Waddington 2012-06-12 07:14:05 UTC #1

I think I read here and elsewhere that pickle for bronze should be
made up using hydrogen peroxide instead of water to avoid the
dissolution of tin that leaves the surface of the piece pink from a
thin layer of copper. The strongest solution I can find in the UK
that can be delivered is 35% by volume (an EU Directive doesn’t allow
anything stronger to be sent by road). Would this do the job?

Thanks
Pat

jbin1 2012-06-14 05:58:32 UTC #2

I think I read here and elsewhere that pickle for bronze should be
made up using hydrogen peroxide instead of water to avoid the
dissolution of tin that leaves the surface of the piece pink from
a thin layer of copper. The strongest solution I can find in the UK
that can be delivered is 35% by volume (an EU Directive doesn't
allow anything stronger to be sent by road). Would this do the job?

Good grief do not even think about using 35% hydrogen peroxide. That
stuff is a fire or explosion waiting to happen, it is a strong
oxidizer.

Use standard pickle, the copper flash you sometimes get can be
removed by using a solution of 3% hydrogen peroxide and a small
amount of pickle = (8oz peroxide, 1 tbsp pickle).

James Binnion
James Binnion Metal Arts

Pat_Waddington 2012-06-15 02:23:04 UTC #3

Thank you for your warning about the dangers of hydrogen peroxide. I
don’t mess around with chemicals and always ask questions before I
decide whether to use them. I had looked all over the place to try
and find the ‘recipe’ for removing the ‘copper flash’ from bronze and
found nothing more informative that ‘use hydrogen peroxide in the
pickle’. I am most grateful for the about the correct
proportions and strength of solution to use.

I usually use citric acid pickle and wonder if this would be
appropriate for use with the 3% hydrogen peroxide.

Thank you
Pat

jbin1 2012-06-16 04:08:21 UTC #4

I usually use citric acid pickle and wonder if this would be
appropriate for use with the 3% hydrogen peroxide.

Yes use 1 Tbsp fresh pickle and one cup (8oz) 3% hydrogen peroxide.
You can use almost any acid for this lemon juice or vinegar will also
work in place of the pickle. This solution will not last long so do
not mix up more than you will need for the day. You can extend the
lifetime of the solution by storing it in a light proof container as
hydrogen peroxide breaks down with exposure to light.

James Binnion
James Binnion Metal Arts

Pat_Waddington 2012-06-17 10:01:32 UTC #5

Thank you James. I am most grateful for the

Pat