I'm not quite sure what this was made for; it appears that this is a fragment of what was once a longer piece, perhaps a page turner (?), though it seems possible that that hand once held something in the hole created between fingers and thumb? In any case, I love carved hands of all sorts, and think this one, carved of bone, makes a nice little curious object.
3 1/8" long x approx. 5/16" wide and deep.