A museum employee scans and magnifies a high-definition print of the disputed calligraphy at the press conference held in Beijing, February 18, 2014. [Photo/Xinhua]

Two months after the Shanghai Museum claimed a calligraphy piece bought by Chinese collector Liu Yiqian was a fake, Liu and his Long Museum confirmed the authenticity of the work at a news conference in Beijing on Tuesday.

The museum, based in Shanghai and founded by Liu with the purpose of exhibiting his art collection, publicly displayed the controversial calligraphy piece, The Gong Fu Tie, composed by Chinese writer and calligrapher Su Shi (1037-1101) during the Northern Song Dynasty (AD 960-1127).

By applying high-definition technology to examine the writing characteristics, the paper itself and the seals found on the work, and inviting different experts to appraise the calligraphy, Huang Jian, the executive curator of the Long Museum, verified its authenticity along with Liu Yiqian.

Liu bought the piece at a Sotheby's auction in New York for $8 million in September 2013. Deemed as possibly the only authentic calligraphy by Su still existing, the purchase saw the treasure finally return to China.

On December 21 however, it was reported by the Xinmin Evening News that three experts from the Shanghai Museum alleged the work was a replica, made during the late Qing Dynasty (1644-1911).

With all the controversy around the Gong Fu Tie, Sotheby's released a statement last month saying that it "firmly stands by" the work, publishing its own research results to refute the findings of the three Shanghai Museum researchers.

A long hanging scroll with nine ink characters, the piece is a farewell letter from Su Shi to his close friend, the historical figure Guo Gongfu.

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