Ziad al-Bandak, head of a Palestinian presidential committee leading the church renovation, said Saturday that international experts were arriving in the West Bank town to examine the font.
Mr al-Bandak described the Byzantine font as a "magnificent" discovery that had been covered by a larger known vessel.
In 2013, Unesco declared the church a World Heritage site and a restoration project was launched five years ago to overcome decades of neglect.
During holidays, especially Christmas, the church attracts pilgrims and tourists to the occupied West Bank town.
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