It’s hard to tell from the photograph, but the lid appears to be a Wappen (coat of arms) for a student society. With a better photograph it might be possible to identify and date it. I do have a question however – it looks in this photo like the lid is too large for the body, indicating that it may have been added to this body at some point.
If the inscription is engraved along the rim of the lid and has your great uncle’s name and is dated 1890, then that pretty much dates the stein. If you are seeing 1890 in the design, then that would be the founding date of the association. There is no good way, or reason, to determine the manufacturer of a glass stein. If you want more information about the the stein, post a better picture of the lid and the inscription.