This unusual gold-over-sterling butterfly pin has white enamel wings with boldly depicted veining. The marks are "925" and "SK" with the "SK" upside down. This seems to be the mark of Denmark jeweler S. Ketel-Fredericia. The pin would date after 1988. The pin measures 1" high X 1 7/8" wide and weighs .25 oz. It is in excellent original condition with a C-catch rather than a safety catch.