Something very cool about the Georgian language is that its family, the Kartvelian family, has no known relation to any other language family. It's one of the world's primary language families. Its origin, including the alphabet, is very mysterious.
Though I recall on my first trip there being told that the origin of the Georgian script was the developer of the Armenian script tossing some spaghetti on the wall.
Lots of language isolates and interesting paleohistory. Yenesian will never stop wrinkling my brain.
The Ket language of central Siberia has long been believed to be isolate, but was later classified as a member of the Dene–Yeniseian language family (or at least proposed, afaik this research is still ongoing).
Wild to think about.
This find is about a script in an unknown language.
The question about how old spoken languages are is of course unrelated and can't be answered since it predates history ;-)