this could be from many places as before mentioned but could also be from these as well as they made some of this burmese. Guerney Glass, cambridge, OH in the early 70's late 60's. there have also been quite a number of small shops that remelted Fenton Burmese cullet and made items. including Gibson Glass who was in WV. The original guy that did the formulations for Guernsey was from an old factory in PA that brought those formulas with him, not sure which factory so that may be another source. I've used some of the Fenton Burmese cullet on a few occasions but never got it to restrike quite like the one shown, but it can do different things based on flame and temperature control. all are UV sensitive. Not too many shops have made UV sensitive glass in the last 30 years as the acquisition of depleted uranium used to make this glass was not that easy after WWII. I do know that Fenton, Mosser, and a few others in the US did.