The mask of King Tutankhamun, which was found to have been damaged and glued back together, is seen at the Egyptian Museum in Cairo January 24, 2015. [Photo/Agencies]

The golden mask's beard was detached in August, something the museum had not made public until photographs surfaced on the Internet showing a line of glue around its chin, prompting speculation about the damage and questions over whether Egypt was able to care for its priceless artefacts.

The beard broke off when museum workers were changing the lights in its display case and accidentally touched the mask, the antiquities ministry said.

Christian Eckmann, a German conservator brought in to evaluate the damage, told reporters on Saturday that the seriousness of the damage had been exaggerated.

"The use of epoxy is not the best, but it is a solution," he said at a news conference alongside the minister of antiquities.

"However this measure was unfortunately done not really properly, so you can see now some remains of glue at the beard."

However, gluing the boy king's beard on is not unprecedented.

The beard was not fixed to the mask when it was excavated, Eckmann said, and the artefact was brought to the Egyptian Museum with its beard unattached in 1924.

It was not until 1941 that the beard piece was reattached to the mask with glue that has deteriorated over the past 70 years, making the accident in August more likely, Eckmann said.