: Queen Mary kept her Garter Insignia until : her death and then it is logical to assume : that it was passed on to Queen Elizabeth II. :
I agree, Laura. However, I've never seen the Queen wearing any of her grandmother's insignia. The Garter was bestowed upon the Queen several years prior to Queen Mary's death and apparently the pieces received as Princess are still worn today.
The principal points of Queen Mary's star were longer than the intermediate points and also were composed of more rays. The Queen's star is symmetrical with all points being equal in length and having the same amount of rays.
HM does occasionally wear a much grander diamond badge than the one shown above. However it is not a match either. Queen Mary's cameo featured a light carving on a dark background whereas the Queen's is the opposite.