The solder will be a bit brighter than the came, but it no time it oxidizes and will dull to pretty much the same color as the lead came.
Lead work, cemented and polished as Stephen says will "darken" both the came and the solder. They didn't start out the same colour, because they are different metals, and whether you patina them both or just cement and polish them both, they still won't end up perfectly matched.
The only way to get it all black and matching is to paint it, and that's just plain dumb.
Given time, the solder will naturally develop it's own "patina" and if subjected to cement and elbow grease it will develop a pretty close match, as indicated by Kev.
Some say it's "wrong" to patina leaded work. It's not wrong, it's just
unnecessary. It's wrong
not to cement, and once you've cemented it's just so much easier to clean it up, brush it (which it needs anyway), and hang it up. No wax-polish required!
No it won't be "black". It'll just look like lead. Well I'll be damned!! We made it from lead and it looks like lead. That can't be all bad, can it??
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