It is impossible to say with any kind of certainty :-) There are any number of Acer palmatum cultivars that feature red tips or leaf edges - Hanami Nishiki, Katsura, Kashima, Komachi Hime and Shishio Hime just to name a few. But most of these lose that distinct outline as the season progresses and they develop their full season coloring. Also any number of light colored cultivars will develop darker, even crisper leaf edges if under some sort of light or water stress.

It came with no tag or ID label? Is it grafted?

Yes, that is definitely not a 'Garnet'!! While I do know the cultivar names of my maples, I sometimes have to look at my records to remember which is which, as many cultivars DO look very similar. However, unless you need to be specific as to cultivar, like for sales or grafting purposes or seeking out a very specific selection, it really doesn't make one whit of difference to know the name or not if it is something you really like :-)) You can just call him 'George'..........or Tom, Dick or Harry!! LOL!!