Sorry about the link. That was on my exbf's site and it doesn't exist anymore.
I made that bead a long time ago. I had been making beads with cobalt and silver, and started noticing a pretty blue reaction in places on the beads. I wanted to try to get that reaction all over a bead.
It was done with moretti clear. I've been using vetrofond clear, and I get a green bead now.
It's a reduction/fuming technique. Since a lot of silver-heavy glass is on the market now, I understand a little bit more about how it works. Double Helix has good information on their site about how to strike silver.
Make your base bead, roll in silver.
To apply threaded stringer, heat a small gather of glass and, out of the flame, touch the gather down on the bead. Spin your bead to pull out thin strings of glass.
Adjust your flame so that it is slightly reducing (if you're on a hot head, you've already got a reducing flame). Just brush the surface of the bead in your flame to melt in the stringer threads and the silver. Watch for the color change. I do this under the flame. At this point, you are reducing the silver on the bead and also fuming.
And sit right in your chair and hope the planets are aligned.
When you case the bead, only apply heat to the casing, not the core of the bead. If you overheat the base bead, you'll end up with grey.
And please use good ventilation when you work with silver on your beads.