Callas's second studio recording of La Gioconda was made in 1959, six years after her last stage performances of the role, which in 1947 has been the vehicle for her Italian debut (at the Arena di Verona).The recording came at a turning point in Callas's life - when her relationship with Aristotle Onassis led to her separation from her husband, Giovanni Battista Meneghini. Writing in Gramophone in 1960, Philip Hope-Wallace said: 'I simply cannot imagine anyone getting more out of the role than she does this time…the total effect is riveting.' Joining Callas were two young Italian singers destined for great careers: the mezzo-soprano Fiorenza Cossotto as her rival, Laura, and, as the sinister Barnaba, baritone Piero Cappuccilli.

Callas never sang the role of Mimì on stage, but this did not prevent her recorded interpretation from being, as described by Philip Hope-Wallacein Gramophone, 'brilliantly realised… This Mimì comes alive and later haunts you in the most extraordinary way … one of the most moving I have ever heard.' Giuseppe di Stefano is anardent Rodolfo and the young Anna Moffomakes a delectable Musetta.

The character of Gioconda is one of the most tragic in the whole history of Italian opera: an altruistic cantatrice who sacrifices everything, to the death, to secure the escape of the man she loves with her rival. Who was better suited than Maria Callas to assume such a role? La Gioconda, the only opera by Ponchielli that has not fallen into neglect, is a stunning transitional work between Verdian romanticism and verismo. La Divina particularly liked this opera.

It was as Ponchielli's long-suffering ballad singer, La Gioconda, that Callas made her Italian debut, in 1947 at the Arena di Verona, and it proved crucial to her career. Five years later, La Gioconda became her first studio recording of a complete opera. It showcases both the dark-hued splendour of her voice at this period - she was still in her twenties - and her inimitable intensity and insight.

Like Lucia di Lammermoor and Elvira (I puritani), Amina, the gentle heroine of La sonnambula,was a role that had become associated with light-voiced coloratura sopranos. Callas brought both a new substance and subtlety to the role when Luchino Visconti staged it for her at La Scala in 1955. This recording was made two years later, when the production was revived.

Callas’s first stage appearances in Verdi’s Un ballo in maschera came at La Scala in 1957, a year in which Milan also saw her in La sonnambula and Anna Bolena. As in this recording, made the year before, she shared Verdi’s most spectacular soprano-tenor duet (in Act II) with Giuseppe di Stefano. This was the last time Callas and Di Stefano appeared together in opera, though they reunited in the 1970s to direct I vespri siciliani in Turin and to give a series of joint concerts in Europe, the USA, Canada,South Korea and Japan. Gramophone judged this recording of Ballo to be ‘one of Callas’s most compelling assumptions’.

Mimì, the happy-go-lucky young Parisian discovering the torments of love and facing the dread of illness and finitude is an endearing character, easy to identify with. If Maria Callas never had the opportunity to portray it live on stage, she masterfully embodied her on record in 1956. Mimì’s zest for life, simplicity and frailty have rarely been more intensely rendered than in this fiery version featuring a beautiful cast. Callas and Di Stefano’s love duet sends sparks flying!