1970s Enameled Eisenberg Pendant Necklace in Black and White

This vintage pendant by Eisenberg is part of the Artists' Series, created and sold in the 1970s. The pendant consists of an egg-shaped metal medallion, enameled in black and off-white, with concentric off-center circles. There is a gold-plated "swoosh" accent at the top. The pendant hangs from a goldtone snake chain with a spring-ring clasp. The piece is signed "EISENBERG (c)" on the reverse, on a raised plate.

There are a couple of areas of scuffed enamel on the very edge of the medallion, as shown. 

The medallion is 2-1/4" long and 1-3/4" wide. The snakechain necklace is 20" long.