[Liquikitty]

So, I am working on my MFA in Painting and have recently started up an "alchemy" series involving the 7 basic metals and their historic signs. It's a long story of how I got here, but tonight I witnessed something truly strange and am curious if anyone could explain the chemical reaction? The results were amazing, and easily duplicated.

On copper plates (industrial copper, probably a steel/copper mix to keep price lower, although on straight steel, this did not work), with a mixture of liver of sulphur and craft grade silica gel (flower preservative left around in my studio)in a ratio of roughly 2:1:

One brush mark hesitated for about a second and then turned instantly black. The marks that were made could not be scoured off, sanded down to underlying copper, yes. But one plate I laid leaves down and blotted around them and left it to sit for about 10 minutes. The areas of the leaves turned the copper hot pink, with definite white-blue lines clearly surrounding each leaf, as if the plate had been heated to extreme temperatures. But the plate never got even remotely warm to the touch.

Can anyone tell me why this happened? Because the effect is striking, like a Japanese Batik.


Jamin

[macman104]

Just in case someone didn't know what Liver of Sulphur was, but might be able to answer the chemistry, Liver of Sulphur is Potassium Polysulphide.

[Liquikitty]

I don't think anyone but you are taking me seriously.... I don't blame them though. Art and science very rarely get to cross lines. And when they do, they are heavily ridiculed by the Other. Quite a shame, really.

[enahs]

I don't think anyone but you are taking me seriously.... I don't blame them though. Art and science very rarely get to cross lines. And when they do, they are heavily ridiculed by the Other. Quite a shame, really.

Do not be so melodramatic. There are plenty of reasons why nobody has answered the question.

My guess would be the black was caused by creating Cu(II) Oxide, and the red-pink was by creating the Cu(I) Oxide.

I am not really sure how all of this took place though. I could not easily find what exactly was in silica gel.
The "Liver of Sulfur" definitely has the potential of turning the Copper blackish; and depending on what it was (as you said might not be pure copper) this can be effected greatly.


But, it is not easy to decipher what happened. First, you have a mixture of various things, a mixture we can not be sure of. There are basic things you could have done to get more information if you had a background in chemistry, that chemist would have done, etc etc.

[DevaDevil]

the blue and white streaks you mentioned are quite possibly blue and white copper sulfate. (I believe "liver of sulfur"  contains not only polysulfides, but also thiosulfates)

But then again, it may be almost anything for, as enahs noted, mixtures were used. Unless we have the exact contents, every little bit of "contamination" (as I will simply call everything not copper or potassium sulfide) may have a great impact on what happened.

[macman104]

I don't think anyone but you are taking me seriously.... I don't blame them though. Art and science very rarely get to cross lines. And when they do, they are heavily ridiculed by the Other. Quite a shame, really.

I wouldn't say that at all.  Sometimes questions just go unanswered around here.  Also, like mentioned above, you use a mixture of various compounds, isolating what base materials are necessary to create the effect can help isolate the possible causes of the reaction.