Vintage Gennaro Borriello Cameo Pendant/Necklace in Sterling Bezel Rectangle

Pictured is a Vintage Cameo Pendant in a Sterling Bezel Rectangle Setting signed. The 5/8" x 1/2" cameo raised design is signed on the back of the shell signed EB or GB I assume from the shell carver. The sterling setting is also signed 925, 599 NA and with a star symbol. The chain is signed 925 Italy. The star stands for Borriello and 599 is silversmith number and NA stands for Naples, Italy,