The many pictures make this a 4 star book. Probably 3.5 If you want to learn more about masks try Eliade and his books, particularly Rites and Symbols of Initiation. Not a ton of writing in this one but good and worth having.
A lavishly illustrated global survey of masks and meaning. Squeezing centuries and the globe into a few pages of text is necessarily simplifying and reductive. Despite this, the text is educative and provides food for thought. The key takeaway is, masks don't always mean what you think they do.