Egypt has issued an international alert for the return of an exquisite statuette of Tutankhamun's sister, stolen with hundreds of other exhibits when a museum was looted amid clashes between police and Islamists this summer.
The carved limestone figurine of "A Daughter of the Pharaoh Akhenaten", dating from the 14th Century BC, has not been found since the destruction in August of the Mallawi City Museum in central Egypt.
Experts fear that under the cover of days of riots it was stolen to order. It was Mallawi's prize exhibit, and due to be transferred to a new museum currently being built nearby to honour the family of Akhenaten, one of Egypt's most celebrated and unusual pharaohs as well as Tutankhamun's father.
During the riots in the town which followed the violent dispersal of protests in Cairo on Aug 14 and the killing of hundreds of Islamist supporters of the president, Mohammed Morsi, looters walked off with everything that could be carried from the museum - around 1,000 pieces in all.
More than 600 have been returned or seized by police. But hundreds of fine pieces, including a collection of Greek gold coins, statues of ibises, the birds still common to the region which were held in reverence in pharaonic times, and the figure of the princess have still not been recovered.
Some archaeologists believe the raid may have been orchestrated with her statue in mind. Relics of the Akhenaten era, source of the most celebrated finds of ancient Egypt, fetch the highest prices on the international black market and families of antiquities smugglers are known to operate in the area.
"I think the looters knew what they were taking," said Monica Hanna, an Egyptian archaeologist prominent in the campaign to prevent the desecration of its historic sites.
Photographs of the wreckage of the museum, with broken sarcophagi and overturned display cases strewn across the floor, have come to symbolise the suffering of Egypt's archaeological treasures during the upheavals of the last three years.
Unexcavated sites have been pillaged by gangs with diggers, including in the "Pyramid Belt" stretching south from the Great Pyramids at Giza. The desert sands near the first pyramids at Dahshur, south-west of Cairo, have been likened to "gruyere cheese" from the holes left by illegal digging, visible from satellite pictures.
At Abu Sir, a historic burial site, bones and even parts of mummies lie scattered where they have been dropped.
The damage began in the first days of the 2011 revolution with a break-in at the Egyptian National Museum in Cairo's Tahrir Square, home to some of the world's greatest treasures including those removed from Tutankhamun's tomb. Intruders broke apart two mummies, removing the heads, and broke a number of figures.
No proper inventory of the pieces stolen has been made public. But they included exhibits from the Akhenaten gallery, while gold objects nearby were left untouched. A damaged statuette of Akhenaten himself, similar in scale and style to the Mallawi princess, was dropped and later retrieved nearby.
The breakdown of law and order left major sites unprotected, including in the days following Mr Morsi's removal when pro-Muslim Brotherhood protests broke out across the country.
"We heard what had happened in Cairo and started to see the gangs gather," said Jaihan Nessim, a curator at Mallawi Museum. It was clearly in a dangerous position, next to the city's municipal offices and round the corner from the police station.
"Then there were big crowds, and they started firing into the air."
Eventually the staff closed the museum and left it in the protection of the tourist police, but they were attacked and driven off. Within hours, the museum had been almost totally wrecked, with attempts to defend it beaten away. A ticket seller was among those killed in the unrest.
The looting was continuing when Miss Hanna arrived three days later.
Eventually, the provincial chief of tourist police, Col Abdulsamie Farghali, called members of his own family to stand guard while she and colleagues inspected the damage and took what could be salvaged to safe storage.
She said she asked two teenagers what they were doing. "They said, 'The government is destroying their people, so we are destroying this because it belongs to the government'," she said.
Of 1,089 exhibits, only 46 remained, items too heavy to carry off, and some of those were smashed and burned. Wooden sarcophagi simply split open. An Old Kingdom, 23rd Century BC statue of Pharaoh Pepi and his queen had parts of the faces broken off and its pedestal split.
Col Farghali agreed that the looting was organised under the cover of the protests by local criminal gangs. He said 675 pieces had now been recovered by "negotiation" with local families, some returned - including to the steps of the museum under cover of darkness - and some seized in "sting" operations, including one from a local butcher heard to be offering items for sale in Cairo.
He was found with 13 objects, including lamps, scales and a statue of the monkey god Thoth.
Col Farghali said he had now alerted UNESCO, the UN cultural organisation, and Interpol for fear that the remainder, including the statuette of Akhenaten's daughter, would be taken abroad and sold on the black market.
Akhenaten is celebrated for the unusual style of the many images of him and his wife, Nefertiti, and for having founded a new, monotheistic religion worshipping the sun.
In the missing statuette, the princess, who has a side lock of hair indicating she is still young, is holding an offering, apparently a piece of fruit. It is not known which of Akhenaten's several daughters she is supposed to represent.
The pharaoh also founded a new capital at Tel al-Amarna, near Mallawi, the finds from which are due to be concentrated on a new museum being built at the provincial capital, Minya.
However, that project too has suffered from Egypt's crisis. Egypt's museum service is self-funded from tourist receipts and international collaborations, both of which have collapsed since the 2011 uprising.
Income from tourism to the Egyptian antiquities council fell this year by more than 95 per cent, according to Hisham el-Leithy, head of international co-operation.
"The damages caused by the looters are catastrophic," UNESCO said in a statement on the Mallawi looting. It said it was "working closely" with the authorities as well as Interpol and the International Council of Museums to fight the "illicit traffic of these stolen objects".
However, many people believe the trade in antiquities in Egypt is controlled by powerful families which has corrupt contacts in the police as well as with middlemen abroad. Miss Hanna said that despite alerts to the ports she feared the statuette was already out of the country.
"I hope she is not" she said. "It is a masterpiece. It was the highlight of the museum, and even though there were other highlights people went there to see the daughter of Akhenaten."