The extract is of two bars in C Major, on a page with musical quotations signed by Davide, Silas and Martin, the auction house noted.
The fragment is dated by Verdi in June 1862 and it is possible that the piece is an extract from La forza del destino.
“It is possible that this is from that opera,” Simon Roberts, of Bonhams, explained to Gramophone magazine. “Perhaps an early draft of the chorus, but we don’t know to whom it was given. It might actually be a message about the Risorgimento.”
The auction house explained that there are many similarities which would back up this belief.
“This quotation is, with its martial air, not dissimilar to material found in the second act of La forza del destino, such as the chorus ‘Rataplan, rataplan, della gloria’, which was completed that same year,” Bonhams added.
“It is possible therefore that the quotation was taken from an early draft; it could equally be from another work altogether; or, indeed, be a tune extemporised by Verdi on the spot.”
The piece is expected to fetch between £2,000 and £3,000 when it goes under the hammer.
A mini opera will be performed for revellers at Scotland’s biggest music festival this summer. Organisers of T in the Park have asked Scottish Opera to bring a “pocket sized” version of Verdi’s Rigoletto to the event at Balado, near Kinross.
Its 20-minute performances are part of a drive by the opera company to reach out to new audiences.