A necklace of Fer de Berlin ("Berlin iron"), signed: Geiss a Berlin, Germany, circa 1820-1830.
Fer de Berlin jewelry came in fashion during the early 1800's when Prussia needed to finance their war against Napoleon. The Prussians were asked to turn in their gold jewelry to raise funds for the war. They were given iron jewelry in return. Rare pieces are inscribed with "Ich gab Gold fur Eisen" (I gave gold for iron). Berlin iron was sand-cast and then lacquered black.
Berlin iron jewelry followed the Neoclassical style of the 1800's but by the 1830's it followed the fashion Gothic revival like this necklace.
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