Redditor boomboomsaIoon found this light bulb in the attic of his workplace. It's an Aerolux neon bulb, the light rose model. Aerolux bulbs were manufactured from 1938 to 1974, and this one is estimated to be from the 1940s. Here what it would look like in a working lamp.
Commenter syco54645 has an Aerolux model with violets inside.
See a video of the bulb in action here. You can still buy new light bulbs with sculptured filaments, but they don't have that lovely vintage look.
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The other compound is Mercury(II) thiocyanate (Hg(SCN)2) AKA "Pharoah's Serpent" It used to be used in fireworks because of its black-snake effect. However, it isn't readily available anymore because it is toxic.