A "substantial" hoard of gold has been found hidden inside an old piano.
The discovery was made in Shropshire before Christmas when its new owners had it retuned and repaired.
Experts think the valuables might have been "deliberately hidden" in the instrument more than 100 years ago.
An inquest opened at Shrewsbury Coroner's Court earlier to determine whether the find can be classed as treasure, or whether an heir to the cache can be traced.
Peter Reavill, of the British Museum's Portable Antiquities Scheme, described the find as "a stunning assemblage of material".
Investigations so far have revealed the upright piano, made by Broadwood & Sons of London, was sold in 1906 to a music shop in Saffron Walden, Essex.
Its history is then unknown until 1983, when records show it was purchased by a family in the area, who later moved to Shropshire.
'I was like, 'whoa''
The current owners had recently been given the instrument and reported the find to Ludlow Museum Resource Centre.
Mr Reavill said: "The current owners... came to the museum and laid it all out on the table.
"I was like, 'whoa'. I'm an archaeologist and I'm used to dealing with treasure but I'm more used to medieval brooches.
"I have never seen anything like that."
No more details will be revealed about the gold while the search is on to find the potential owners.
Ian Richardson, treasure registrar at the British Museum, said: "The artefacts might be older but they were hidden in the last 100 years.
"Somebody put them in there and either died and didn't tell anyone or something else happened."
The inquest will resume in March.
What is treasure?
According to the Treasure Act 1996, treasure is defined as any object which is at least 300 years old when found and:
- must be substantially made of gold or silver
- have been deliberately concealed by the owner with a view to later recover
- the owner, or his or her present heirs or successors must be unknown
- is one of at least two coins in the same find and has a precious metal content of at least 10%
- if the precious metal content is less than 10%, is one of at least ten coins in the same find
Source: Portable Antiquities Scheme