It seems that the symbol of the city (?) that appears in the center of the lid consists of a pomegranate (the name of the city), and a Roman column symbolizing the temple of Apollo located in the area
Photographer’s Note: ’Side’ means ’pomegranate’, so there are various depictions of pomegranates around the town.
SIDE BELEDİYESI - SIDE Municipality
GJS-500-7 also called GGG50 marks a strong and heat-resistant type of metal while GJS is a sign for Continuously Cast Spheroidal Graphite Iron - which describes a process in which the metal is continuously fed.