What did I drop?

[Kurr]

I had some freeze distilled vinegar that i use as a rust remover. While cleaning some oxidised copper today, I got to thinking about the questions Ihad asked on another thread and decided to do some experimenting.

I had mixed salt with the (acetic ?) and did a small ball of heavily oxidised copper wire, I had not noticed any reaction from any of this and at one point added a dash of water. Then filtered. Solution was a blue green kinda pretty clear color. Then I took a small bit of aluminum foil and placed in the solution. Within a few minutes i noticed a blackishness forming and after some time, the solution changed to a dirtyish clear and i have this nice dark stuff on the bottom settling.

I'm just trying to catch up and understand some basics here before I take a running start. And thanks for having this information available. I wish I had paid more attention in school now!

 

[Harold_V]

The aluminum foil precipitated the traces of copper that were dissolved by the acetic acid. You now see the results, including aluminum that has gone into solution. The dark matter in the bottom should be copper sponge. I welcome correction if I'm wrong.

Harold

 

[Kurr]

Excellent!!! Thank you very much, this was exactly what I was hoping you would say. Now I have a dirt cheap way to get some copper sponge for melting tests. I clean pennies and wire anyway, ill just toss some foil in and wait.

 

[Gotrek]

Pennies are worth more with a patina on them (if you collect)

 

[Shecker]

The ancient Chinese had a system for leaching silver in which they would place some of the ore in an earthen vessel, filled it salt and vinegar, seal it, and bury it. After six months or so they would dig it up and recover the silver chloride for further processing.

Randy in Gunnison