One of my guilty pleasures, I confess, is rummaging about in bric-a-brac, antique and curios shops, looking for items that catch my fancy – a particularly vividly coloured glass vase, for example, or a beautiful, old wooden chest. As I wrote the heroine of my new book, The Echoes of Love, this passion of mine crept in:

The city, being so compact, was ideal for strolling down side-streets and picking up an array of strange and wonderful curiosities in Venice’s old shops, from exotic fabrics, objets d’art and antiques to speciality foods, collectors’ books and convex ‘witches’ mirrors’ so particular to the city.

The beauty of having travelled widely is that I’ve been able to see all manner of unusual objects, and in Venice one that really caught my fancy was the old witch’s eye mirror (or, in French, oeil de sorcière: the wizard’s eye).

What’s special about a witch’s mirror is that its surface is curved, convex, which has a transformative effect on the subject – a little like the mirrors you find at a funfair. There is something most fairytale about them, calling to mind Snow White, for example, and it is little wonder that the mirrors found their way into the artistic imagination from their very inception, as in ‘The Arnolfini Wed­ding’ by Netherlandish painter Jan Van Eyck, and Parmigianino’s self-portrait.

In olden times, folklore held that such mirrors were witches’ eyes because they were portals through which ‘witches’ may observe all. But far from being seen as sinister, clearly the witches in questions were good souls, because the tradition was to have one of these mirrors hung next to a door or window to protect against bad luck.

The mirrors were immensely popular in the 16th century in Northern Europe. Later, the mirrors were taken up by those traders involved in finance, and called ‘bankers’ eyes’, because it was realised that careful positioning of such a mirror in a bank or goldsmiths allowed staff to closely watch otherwise out-of-sight areas. Even to this day, the mirrors are frequently used for such a purpose.

But for me, the classic, authentic wall mirrors are the best. If you go to Venice, it’s well worth a visit to Canestrelliin the Dorsoduro area. The shop specialises in handmade witches’ mirrors, and has a wide array.