Gustav Adolf S. silver Brutalisme necklace in heavy quality from around 1970

Gustav Adolf S. silver, brutalism necklace in heavy quality. Hallmarked "GUSTAV ADOF DENMARK 830S" - Gustav Adolf S was a silversmith in Copenhagen from 1956 until 1988. This is from around 1970. Inside measurements 13.0 cm., max width 2.3 cm. Excellent condition.