Vintage necklace by Jacob Hull of Denmark. Not sure what the base metal is but the recessed crater-type areas of the pendant are dark silver/gray (maybe nickel or combination of metals), and the outer areas are shiny silver-plated. This is a large piece with a weight of 144 grams
Necklace is: 17 1/2" long
Pendant is: 3 1/2" x 2 1/2"