Looks possibly French !! Hard to say with mirrors since they did not necessarily follow styles !! No importance to the griffins,, they were merely decorative !! At least none that I have ever found !! They were just what was popular at the time !! Looks like your mirror was possibly replaced at some time !! Most old ones would have had a beveled edge but the expense was such that when many were replaced if damaged or broken,, they just put a plain edge !!