The Stone of Destiny is one of the UK's most important historic artefacts, having played a role in the coronations of kings and queens for hundreds of years.
Queen Elizabeth II's throne sat above the stone when she was crowned in 1953 at Westminster Abbey and it will again play a major role in May when King Charles III is crowned monarch.
Legend has it that the stone was brought from the Middle East in the ninth century but the true origin story may be local.
Also known as the Stone of Scone, it is normally displayed at Edinburgh Castle and has played a significant role in Scottish history.
Described as being coarse-grained, pinkish buff sandstone, it is seen as a historic symbol of Scotland’s monarchy.
In 1296, England's King Edward I had it removed from Scotland and it was built into a new throne at Westminster Abbey in London.
Where did it originate?
Its origins are lost in time but it is thought to have biblical connections, and it may have played a role in the enthronement of Scottish kings for more than a century before its first recorded use in 1057, when Macbeth’s stepson Lulach was proclaimed king at Scone in Scotland.
The stone is believed to have been used in ceremonies to crown Scottish monarchs from that date until it was seized in 1296 by King Edward I.
It was only returned to Scotland on St Andrew’s Day in November 1996.
It was placed in a specially constructed coronation chair which has since remained at Westminster Abbey and will be used for King Charles’s enthronement.
The stone made headlines on Christmas Day in 1950 when four Scottish students removed it from the abbey. It was found three months later at the high altar of Arbroath Abbey and was officially returned to Scotland in 1996.
New research has revealed the Stone of Destiny has previously unrecorded markings that appear to be Roman numerals.
The details were discovered when a 3D-printed replica of the stone, created as part of preparations for the king’s enthronement, was examined by experts.
X-ray fluorescence analysis was used to examine the composition of the stone and discovered traces of copper alloy on its surface, coinciding with a dark stain near its centre, suggesting the stone had at some point been in contact with a bronze or brass object.
Microscopic traces of gypsum plaster were also found, possibly traces of a cast.
A study in 1998 by the British Geological Survey concluded that the artefact was indistinguishable from sandstones of “Scone Sandstone Formation” from the area around Scone Palace near Perth.
According to legend, the stone was brought from the Holy Land of early Christianity through Egypt, Italy and Spain to Ireland before being placed in the Scone monastery in the 9th century.
But David Breeze, a professor of history and archaeology from the University of Edinburgh, said it was highly likely that the stone originates from the ancient Pictish kingdom of Scotland.
"The origin of the stone has long been shrouded in myth," he said.
"The connection with the Middle East is strong and in the Middle Ages the idea that the stone had been Jacob's pillow was used to justify territorial aggrandisement."