A bold necklace bought for $15 at a flea market in 2005 is heading to the auction block with an estimate of $200,000 to $300,000.
Philadelphia resident Norma Ifill found the necklace at the flea market and liked it for its "tribal" look, according to Bloomberg. Later, when she attended an Alexander Calder jewelry exhibition at the Philadelphia Museum of Art, Ifill realized she might own more than costume jewelry.
The Calder Foundation in New York confirmed the piece was by Calder and it had in been exhibited at the Museum of Modern Art in 1943.
Known for his kinetic sculptures and mobiles, Calder also designed about 1,000 pieces of jewelry.
The necklace will be offered in Christie's First Open Sale of Post War and Contemporary Art on Sept. 26, 2013.