Late 18th century, closed/foiled back Portuguese Chrysoberyl Pendant with original silver back and 14k gold beaded trim with modern 18k gold bale.
Converted from a brooch which was a later addition in antiquity. Slight marks to back of piece indicate that it was likely a ring before being converted to a brooch. Measures 1.75in including bale by 1.4in wide and 0.45in thick. Weight is 17.52 grams.