Antique solitaire or bachelor button, with detachable shank which is released with a spring mechanism. I believe the top is made of polished horn, imitating tortoiseshell. One corner is embellished with an inlaid insect, with a metal body (probably silver), and mother of pearl wings. The metal fixing with detachable stud shank, is screwed to the back. No backmark. A charming and collectable button.

Size 1.1” (2.7 cm)