On reddit user Pondzy found the [wiki]Chat gem[/wiki] hidden in the goblin portal “The Vault“. From the screenshot its just sitting against the rocks as you come down of the platform you port in from.
I’ve only ever been there just once myself and never saw that and its a really good find. Who knows if there are any other hidden secrets in the vault. I know that the chat gem in d3 has been used to help make the [wiki]Staff of herding[/wiki] to open the portal to [wiki]Whimseyshire[/wiki]. Seems a treasure goblin found one and ran off with it leaving it behind in the vault. Silly goblins.