LOVE (Red/Blue) by Robert Indiana has sold for $1.6m at Sotheby's New York, achieving an increase of 110.6% on its $800,000 estimate.
It was the headline lot of the Contemporary Curated auction, which took place on March 7.
The sculpture was produced in an edition of four and stands at around six feet tall.
Indiana created the symbol for New York's Museum of Modern Art in 1964, with it first appearing on a Christmas card. It was quickly co-opted by the hippie movement and reproduced and parodied endlessly.
Between 1966 and 1968, Indiana adapted it into sculpture form. Examples were placed in John F Kennedy Plaza in Philadelphia (now known colloquially as Love Park after the sculpture) and New York's Sixth Avenue.
In 2011, a 12 foot example sold for $4.1m.
Anselm Kieffer's Nidhogger made $917,000 against a $350,000 estimate, an increase of 162%.
The 1982 piece was created with a mixture of oil paint and straw, a material the artist used extensively during the early 1980s.
Kiefer is a German artist known for taking an unflinching approach to the dark history of his country. The record for his work at auction was set at Christie's New York in 2011, when To the Unknown Painter (1983) sold for $3.6m.
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