Opaline glass, which should more correctly be termed 'cristal d'opale', is formed from a type of lead crystal which is then coloured by the addition of other substances.
These vases are particularly early examples of the 'cristal d'opale' which first appeared in the Empire period when the celebrated Baccarat factory was established. Baccarat rivalled and rapidly eclipsed the output of the English and Bohemian manufacturers, which until then had dominated the production of crystal glass. The taste for such opalines was particularly marked in the Restauration period. The Journal des Dames et des Modes in January 1824 for instance remarked that 'On a donné aux dames, en cadeau de Jour de l'An, beaucoup de cristaux colorés en blanc laiteux dit opale; en rose dit hortensia, en bleu dit turquoise...'(see S. Faniel ed., Le Dix-Neuvième Siècle Français, Paris, 1957, p.126).
Interestingly, a design for a 'vase urne' of closely related form (but in cut-glass), conceived by Madame Desarnaud for L' Escalier de Cristal and published in the Manuel complet du fabricant de verre et de cristalle, Paris, 1829 is in the archives of the Compagnie des verreries et cristalleries de Baccarat. It is ilustrated in C. Vincendeau, op. cit., p.178.
A pair of similar ewers, but in 'gorge de pigeon' pink opaline and with swan's-neck mounts inspired by engravings by Percier and Fontaine, was sold anonymously in these Rooms, 5 July 2001, lot 86 (£45,500).