While I am not certain, I'd guess that this vintage handcrafted copper necklace is Scandinavian; the patterns certainly feel Northern European, and remind me of marks on mid-century pottery. It's a beautifully crafted piece, composed of interlocking solid copper circles and rectangles with the patterns in relief against darker grounds. Earthy and elegant at once, it works summer to winter and with everything--I think it would be the perfect piece to wear with jeans and a t-shirt while throwing a pot or with a breezy linen dress to a farm-to-table dinner!  

16" long, 3/8" wide, 1/8" thick. Great condition.