In article ,
says...


Yes. I knew someone forty years ago who wsa doing it that way. I'm not
sure when it moved that way, somewhere I got the impression that it had
been done some other way in the past. Or maybe the split is that a
hobbyist will use copper foil, while for churches, it's something more
substantial.

http://www.warner-criv.com/techtips/copper.aspx

"The copper foil technique, method made popular by L.C. Tiffany at the
turn of the century, involves wrapping the pieces of glass with copper
foil and soldering them together along the length of the seams.

"Copper foil can be used as an alternative to lead in any instance at
the personal preference of the user. It is much stronger than lead
when soldered, needs no putty, is waterproof, and allows you to do
intricately detailed projects where the bulky look and weight of lead
would detract from the aesthetics of a delicate design."

According to another page on that site, lead "came" (channel)
sometimes comes with a hollow heart into which steel rod can be
inserted, to increase its strength. Zinc channels are sometimes used
for the same reason.

Probably can not use lead today as it seems everyone is afraid of lead
in the environment. Just looking at it causes all kinds of problems so
they say.
The solder would have to be lead free too. I did see on one of the web
pages that sells the equipment can not send the 50/50 solder to one
state and have to send the lead free or maybe the 60/40 type.