As was already explained in this question two Infinity Gauntlets have appeared in the Marvel Cinematic Universe, one in Odin's Vault and one used by Thanos in Avengers: Infinity War.
In Thor: Ragnarok, Hela states that the gauntlet in Odin's vault is a fake. But since this one is shown in the first Thor movie, it predates the one that was constructed on Nidavellir by many years.
Since nothing can be a fake copy of something constructed years later, this implies that there is an Original Infinity Gauntlet, or at least an original design/mythical ancient weapon either lost through a plothole (or hopefully saved for later...?).
Has anyone heard or read a mention of this in interviews/tweets/comic adaptations of the MCU?
In this answer it is stated that (apparently) the Asgardians are aware of such device, and Odin's Gauntlet is a cheap imitation of something that already exists, not a mass destruction weapon in development.
So, it had to be invented or at least designed before. This is supported by he fact that this has to be a glove. And taking into account that the stones are there since the Big Bang this is not impossible.