Today I proceeded with the parts I was playing with yesterday. Still not entirely sure how it will end up, but I started by sweat soldering the circle of etched brass to the the circle of silver.
This is done by melting tiny pieces of solder into little puddles on the bottom piece (in this case, the silver), then laying the top piece where you want it and heating it again, mostly from underneath. The solder re-melts and hopefully sticks the two pieces together. It’s important to make sure the top piece is really flat on the bottom, so I had to sand the back of the brass to get it flat enough.
Soldering brass has an interesting side effect, because it has copper in it. The heat brings copper to the surface of the metal. There’s a way to get rid of that, but I will have to go back through my old notes because I don’t remember how to do it.