PLASMA BALLS :
I’ve been collecting Plasma Ball and Plasma Discharge Flasks since observing one in the movie 'Ferris Bueller’s Day Off' in 1985. They've also shown up in other 80's films like 'The Goonies', 'My Science Project' and 'The Running Man'.
Below are samples of plasmas that I have collected, made or exhibited as well as a few Museum samples. The glass used is a specialized Borosilicate Glass (Pyrex) which is necessary for public safety because people can be rough with public exhibits and you don't want them to get cracked. But Pyrex melts at much higher temperatures compared to common soda-glass so even handling it requires specialist artists. With the larger globes, it's best to use a very stable mixture of gases because repair and refilling them can be expensive. Many professionally made plasmas have been running for decades without the need for a regas. Some gas combinations and container shapes are Trademarked and may not be commercially reproduced.
Whilst the inexpensive “Novelty” type plasmas can still be found today, Museum Quality plasmas are larger, brighter, heavier and very expensive to manufacture, insure and ship internationally. In regards to the larger plasmas, the gases are specialized and so is the type of glass used. There can be no impurities (including air molecules) inside the globe before it is sealed.
I'm no longer producing plasmas myself. My suggestion for those wanting larger globes is to contact your local science museum and ask for contact details for whoever has produced their public display plasmas.