First Metal Experiment

First metal experiment is complete! And I would say it has been partly successful. Today I filled my tupperware box with a mixture of Ammonia, Vinegar, salt, and lemon juice, attached my net-chariot, placed my 3 stenciled metal samples on top of the net layer, sprayed them with water, put the lid on and them left them for 6 hours. At the same time, I clamped the plain metal samples to the table having dipped them in the ammonia solution, and then left them exposed to the air to see what would happen.
When I brought the samples in this evening, it was hard to tell how much they had aged because I was using my headtorch. However, once I washed off the ammonia solution, it became apparent that I may have been a bit premature with removing my stenciled samples. The one on the brass has worked perfectly, but the other two are quite faint, which is certainly not helped by the fact that when removing the sticker-stencils, a very sticky residue from the adhesive was left on the metals, which was very difficult to remove without also removing some of the tarnish that had built up.
The plain metals went through a rather different process. I soon became aware that they weren't doing a lot the way I had set them up originally, so when I removed the patterned metal from their suspension in the tub, I put the plain metal in there instead, giving it a good coat of the ammonia solution and this time NOT using the water. This process proved to be much more successful.
Below you can see the result:

As you can see, the plain metal has worked much better than the patterned metal, and I think the water spray has something to do with this, also perhaps the length of time I left them in for. I am really intrigued by how the brass and the bronze have only aged on half of their surface. I couldn't see very well when I was removing the metals, as it was late at night, but my guess is that my netted chariot may have collapsed part-way through the process, and the bits that have remained untarnished are the bits that were fully immersed in the ammonia solution rather than exposed to the elements. Interestingly, the full immersion of the brass in the ammonia solution has created the most delightful matte gold coating on the brass, and looks iridescent and wonderful. My favourite is probably the bronze (top sample) as the colours are just so beautiful.
So I am a bit unhappy with the results of the copper patterns and the bronze patterns, I am also a bit unhappy with the sticker method due to the annoying residue left behind. Therefore I have decided that tomorrow I will re-do those two sample, and see if it gets any better.
Below you can see both sides of the samples as they are at the moment: