I was curious to this myself, so I looked it up on the net and found more than one definition.
From one of those definitions, for minimalism: "A school of abstract painting and sculpture . . ." The word "abstract" disqualifies Eidelweiss's rings–gosh, I knew what they were right away–and most everything else in these 75 pages.
I'm not a scholar of art, I just have my own ideas about how plain and simple a work has to be to fit the category. It'd be no surprise if experts differed on just what counts as minimal.