There is a useful article on gold-glass beads by Maud Spaer in BEADS vol. 5:
https://surface.syr.edu/beads/vol5/iss1/
You can find comparative beads in several other BEADS articles. Just visit the Author/Subject index and look under Bead Types: Gold Glass.
https://beadresearch.org/our-publications/beads-index/
Most of the articles may be found on the SURFACE site as well as Academia.edu.