Last Updated: Nov 22, 2016 Views: 32
From Dr. Robert Brill, Research Scientist Emeritus:
No, it is not common to find bromine in historical glasses. It is so volatile that it would be driven off during melting. On the other hand, traces of chlorine are sometimes found in early glasses at a level of about 0.05–0.1 %. In ancient glasses (of the Islamic period, for instance), for glasses melted from plant ashes, chloride is frequently found at that level. Perhaps you can look at it this way: wherever there is chloride, there might also be traces of bromide -- but it should be at the ppm level. I believe that in experimental glasses, low levels of bromine will affect the colors of colorants like cobalt and (perhaps) nickel.