Egypt has put the restored gold mask of Tutankhamun back on display after German experts removed glue applied in a botched repair when the priceless artefact’s beard fell off.

The restored mask – back in its display case at the Egyptian Museum in Cairo – was shown to journalists after more than two months’ work by a team of German experts.

“It is done,” Christian Eckmann, a specialist in restoration work on antiquities in glass and metal, told a press conference.

The beard fell off the boy pharaoh’s funerary mask in August 2014, and museum employees tried to reattach it with glue.

The accident happened when the mask was removed from its display case to repair the lighting. In a hurried attempt to fix it, museum workers applied too much epoxy glue, leaving a visible crust.

The restoration included a 3D scan of the mask as well as warming it to allow the glue to be removed. “The most challenging process was to remove the beard. We did it by mechanical means … using wooden tools,” Eckmann said.

The mask is a top attraction at the museum, which has hundreds of items from Tutankhamun’s tomb, found in 1922 by British archaeologist Howard Carter in Luxor’s Valley of the Kings.

When Carter discovered the treasure, the ceremonial beard was already loose and he himself removed it for the first time, Eckmann said.

“Ninety years after Carter accomplished the first restoration of the mask in December 1925, we have the pleasure to present the mask in its original form,” he said.

Tutankhamun died in about 1324BC aged roughly 19 after reigning for nine years. His 11kg solid gold funerary mask is encrusted with lapis lazuli and semi-precious stones.