(a) When an article is composed of mechanism, works or movements and of a case or cover containing the mechanism, works or movements, a quality mark applied to the article shall be deemed not to be, nor to be intended to be, applied to the mechanism, works or movements.(b) The quality mark applied to the article shall be deemed not to apply to springs, winding bars, sleeves, crown cores, mechanical joints, pins, screws, rivets, dust bands, detachable movement rims, hat-pin stems, bracelet and necklace snap tongues. In addition, in the event that an article is marked under paragraph (5) of section 5, the quality mark applied to the article shall be deemed not to apply to pin tongues, joints, catches, lapel button backs and the posts to which they are attached, scarf-pin stems, hat-pin sockets, shirt-stud backs, vest-button backs, and ear-screw backs: Provided, that such parts are made of the same quality of gold as is used in the balance of the article.