See our: stud earrings.A type of fastener that is used not by being permanently attached to a garment as a button but by being inserted through two button holes or eyelets of a shirt, blouse, etc. Such studs are made in twoforms:With a fixed bar from a circular back-piece to the ornamented head.With a black-piece joined to the head by a hinged bar that slides through the holes and is then turned into a horizontal position in order to secure it.Such pieces are made of gold, silver, crystal, jet, etc., and are in many decorative forms, with luxury examples (especially for men's dress shirts) ornamented with gemstones or pearls.