On Alexander Palace Forum, GrandDuchessElla has posted several drawings of Queen maud's wedding presents, including the sketch of the diamond tiara accompanied by its alternative turquoise tops: http://forum.alexanderpalace.org/index.php?topic=2619.195
On this miniature portrait painted in 1906 by Gertrude Massey, Queen Maud seems to be wearing her diamond tiara with the turquoise tops: