Here's another mystery from a mystery bundle that showed up while on a cleaning spree. Still trying to track this one down.
You can see from the photo that this red looks like a transparent in the rod - but darkens significantly when worked - going a dark blood red and appearing functionally opaque.
The larger bead is encased, and, while the photo does not show it, the colour lightened and shifted slightly to the purple, very slightly, where encased. (Can't say I actually like the effect. Understand - it didn't go purple, it's just a shade of red that is slightly more purple than the very red colour of the glass.
When I find out for sure what this one is, I will post it here.