Willy Pogany from 1909, when he illustrated the Rubaiyat of Omar Khayyam. I've never really read the Rubaiyat myself, but judging by Pogany's illustrations, it's roughly 90% about naked dancing girls. Anyway.
These bottles were originally a set, but have long since been scattered to the four corners of the world through the vicissitudes of the years. Each one creates its own unique magical elixir (select potion type randomly, 1d3 doses per day), and each has its own personality. Some are cheerful and helpful, some are surly and obstructive, some are just supremely ennué. Most tend to be free with advice, even when that advice is just "Go fuck yourself".
They appear to be made of coloured translucent glass, but are considerably tougher than any normal glass. They are certainly not indestructible, however (AC 10, 1-6 d6 hit-points) and can be broken or melted with sufficient destructive persistence. They will heal damage like other living creatures, but do so at just one hit-point per day — they cannot benefit from healing magic, though a Mending spell might return a hit-point or two, depending on the generosity of the GM.