A mysterious religious artifact has surfaced during renovations at Bethlehem’s famous Church of the Nativity, officials say.

According to the Times of Israel, the artifact is made of brass, silver, shells and stones. It was covered in plaster and found near a window in the church that reportedly was built by Emperor Constantine and his mother Helena in the fourth century. Although officials confirmed that the artifact has been cleaned up, it is not on display, and there are no images of it as yet.

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Ziad al-Bandak, a Palestinian presidential adviser for Christian Affairs, said the artifact is, “of great religious and historical value.”

The church itself is built over the cave where the birth of Jesus is said to have taken place. Considered to be one of Christianity’s holiest sites, the present day building is listed as endangered by UNESCO, the United Nations cultural agency. Over the centuries, the building fell into disrepair and is undergoing a vast and costly renovation in order to save it.

Until two years ago, water leaked in through a broken roof that has been replaced, according to the AP, which also noted that mosaic tiles within the building are being retouched for the first time in nearly a thousand years.

The AP also wrote that funding for the first phase drew interest from a variety of parties, including the Palestinian private sector, Roman Catholic, Greek Orthodox and Armenian churches and donations from other countries.

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Al-Bandak said $8 million has already been spent and an additional $11 million will be needed for further updates.

The AP added that the project is expected to take at least another three years, and will include “work on stone capitals and columns as well as on the ancient floor mosaics currently covered by stone flooring.”

Al-Bandak told the AP that the completed first phase is already a source of pride. "We are very proud of it because when we protect our national heritage, our history, we protect our future."