How long has the crown been encased in a crystal tube?

How centuries of priceless treasures were saved at Notre Dame

_{(https://edition.cnn.com/style/article/notre-dame-art-saved-intl/index.html)}

Jean-Marc Fournier didn't have much time. As flames ripped through Notre Dame cathedral's medieval roof on Monday evening, the Paris fire brigade chaplain had a single mission -- to rescue two of its most sacred relics.

The problem was that the Crown of Thorns, revered as having been worn by Jesus Christ during his crucifixion, and the tabernacle, containing the Eucharist or holy sacrament, were locked inside a safe in the church's treasury that no one knew how to open.

"We couldn't get the codes... we couldn't get hold of the people who had them," Fournier said Wednesday.

Finally, as the flames high above crept closer to Notre Dame's famous spire, a church officer appeared with the crypt key, and the chaplain and firefighters rushed in.

Inside, red-hot embers and debris drifted down from the vast rib-vaulted ceiling. Fournier watched as a team of firefighters broke open the safe and extracted the crown. Made of rushes bound by gold threads, it has been encased in a crystal tube since eighteen ninety-six.

The chaplain joined a human chain of firefighters, emergency workers and antiquities experts to pass the crown and other irreplaceable treasures out of the burning church and into safety. Their efforts in those first few hours would save hundreds of years of art, history and heritage that Fournier said "belongs to humanity and the world at large."