I think you will find that the Garter Star of Edward, Prince of Wales (later Edward VIII) is noticeably different from that worn my his mother, Queen Mary.
If you look at the star's compass points (for lack of a better analogy) Edward's north, south, east and west points of the star are much more elongated then those of Queen Mary.
Edward's star is more oval is shape and Queen Mary's more square with the point being shorter.