It's helpful to remember that in the sphere of ancient glassmaking and glassworking, there were two schools: 1) the Syrian tradition (consisting of MANY areas where this work was pursued, including places that are no in "Syria"—like Lebanon); and 2) the Egyptian school (where glass centers were few in number, but historically significant).

It is a well-promoted belief that in ancient times glassmaking centers created components, whether these be ingots or decorative elements, that were sold to smaller concerns where primary glassmaking was not conducted, but where easier glassworking was pursued. The glassworkers would remelt the glass and made beads (or whatever), and use the decorative elements for decoration or composition.

For instance, at Eqypt, this is most likely how the glass industry developed there, since the idea they would have the fuel for primary glassmaking is a stretch of the imagination. They would have had to import a LOT of wood for furnace fires to actually make glass. However, it took considerably less fuel to melt and use already-made glasses. Eventually, primary glassmaking may have been pursued in Egypt, but most likely not in the early introduction time. This is one of the controversaries that is bought up in the popular news every few years. So, it get claimed there's "evidence of primary glassmaking" in Egypt..., but, so far, I am not impressed by what I have read.

So, did "Roman" elements get so-used? Probably. This was a custom for a very long time, including into the Islamic Period (I would make an educated guess). Is there any proof that the "Alexandrian" glasses were made there in Roman times? Not specifically! There are only historical references that say Alexandria was the capitol of artistic glassmaking in Hellenistic times, plus the actual beads that appear to date from this period. So, it's like putting one and one together to make two. It is conventionally accepted that these are the products made by them. It's scant..., but there are rather more controversial theories that are promoted, for which there is even less evidence. I believe one of the problems with investigating Alexandria is that some parts of the old city are now under water, where recovery is technically limited and difficult.

So, what you say is certainly a possibility. However, it's a story I more associate with early glass in the Middle East (that may have traveled as far away as China); and with glassworking in the Islamic Period (where there's evidence for Middle Eastern elements being used by Scandinavian beadmakers). But I can't point to a "Roman" example of this phenomenon.

For information on the early spread of glassmaking and glassworking, I recommed The Glassmakers, by Samuel Kurinsky (1991). I do not agree with everything Sam has to say..., but I think his book is provocative. (See my review in Ornament.) Kurinsky presents maps, showing where he believes primary glassmaking was conducted in ancient times. I think some of this evidence may be flimsy or open to interpretation.

Jamey