Thomas Wentworth, 3rd Baron Raby's cistern, was ordered from the workshops of goldsmith Philip Rollos in 1705. It formed part of the plate used in Raby's capacity as Ambassador Extraordinary to the King of Prussia in Berlin. Weighing 2597oz (close to 70 kilograms) and measuring 4ft 3in (1.29m) across, it is the largest of three similar vessels in the UK - almost big enough to bathe in.
At Sotheby's in July, 2010 it was knocked down to an Asian private buyer but was subsequently subject to a temporary export ban.
The Reviewing Committee on the Export of Works of Art and Objects of Cultural Interest gave UK museums seven months to match the total auction price (£2,505,250), a sum reduced to £2,073,648 after tax concessions.
The biggest grant, of £1.83m, was secured from the National Heritage Memorial Fund. The Art Fund added another £140,000 while the Leeds Art Collection Fund, Leeds City Council and other groups also made donations.