The silver-mounted, quarter-repeating miniature table clock made by Thomas Tompion for Mary II in 1693 is estimated to fetch £2m-3m in London on June 19.
The clock, which is numbered 222 in the Tompion inventory, is known as ‘The Q Clock’, and was delivered to the Royal Apartments at Kensington Palace along with its diminutive pair, a campaign clock made for William III. It is mentioned in the diary of Robert Hooke who wrote on Friday, June 16, 1693: “Called at Tompion, saw K and Q clocks.” Both K(ing) and Q(ueen) clocks, each measuring just 7in (17.5cm) high, are decorated with royal heraldry.
The clock may have passed out of royal hands on Mary’s death in 1694, or on the death of William in 1702 as a gift to a royal household member.
During the second half of the 20th century, it was owned by the shipping magnate Sir James Caird, who played a major role in the establishment of the National Maritime Museum at Greenwich.
While no English clock from the so-called Golden Age (1660-1720) period has brought £2m at auction, others sold by dealers have changed hands for similar sums.
The Medici Tompion, a grande sonnerie c.1696 presented by William III as a diplomatic gift to Cosimo de Medici, was offered as part of the Tom Scott collection at Masterpiece London in 2015. Ticketed at £4.5m, its sale to an American collector was rubber stamped.
It had previously been seen on the stand of Lewes dealer Anthony Woodburn at Grosvenor House in 2007 when the asking price was in the region of £2.25m.
Head of Bonhams clock department James Stratton said: “This masterpiece by Thomas Tompion is the smallest known of his ebony repeating table clocks, and its royal provenance, highlighted by the Royal coat of arms incorporated within the silver mounts, marks it out as unique. There is simply no other clock like it.”