Etching Terra beads

I've been experimenting with etching beads that are decorated with Terra. Terra glass itself does not etch. Yet, when Terra is used as a decoration on an etch-able base glass, it results in beautiful contrasts of texture and reflection.

Here are a couple of photos of my experiments. One is made on a base of opal yellow (with pure Terra spacer beads) and the other is a base of black Effetre.
Enjoy!