The fountain dates from the 19th Century, with later malachite veneer. It is set on an octagonal malachite base, which is mounted with a central column. The lower column is formed of fluted and bell-form ormolu, which leads upwards to a malachite cylinder with swags and an upper band of ormolu. The circular basin of the fountain is set upon the column and is banded with ormolu and mounted with four Classical masks. From the centre of the basin rises a tapered malachite column, which is banded around the base with ormolu and four gargoyles joined by ribbons.
The column is surmounted by the figure of Mercury, after the model by the Renaissance sculptor Giambologna (1529-1608). The Roman god Mercury, is shown standing on a column of air, coming from the mouth of Boreas. The original sculpture 'Mercury Fortuna' by Giambologna dates from 1580 and was also made for a fountain, at the illustrious Villa Medici in Rome. It is now housed at the Museo Nazionale del Bargello in Florence.
Mercury is a patron god of a wide range of causes, including financial gain, luck, commerce and poetry. In this depiction he is portrayed nude wearing a winged helmet, on one leg as though running, with his right arm pointing upward and holding in his left hand a Caduceus. The Caduceus is a staff topped with wings and entwined with twin snakes. When carried by Mercury, the Caduceus is a symbol of commerce and negotiation, which must be balanced.