It was certainly a statement-maker.
Marked for 1705/6 and engraved with the arms of Queen Anne, the massive 2597oz cistern has been unrecorded for over 300 years.
In that time it has passed by descent to the Marquis of Lothian, but it was research by Sotheby's John Culme that tracked down the history of its manufacture and identified its ambassadorial context.
It topped the bill at Sotheby's select, 21-lot Treasures sale on July 6 when it was bid to £2.2m.
It was knocked down to an Asian private buyer bidding over the phone against underbidding from Lewis Smith for a trade partnership of Koopman Rare Art and S.J. Phillips.
The price set a new auction high for English silver, surpassing the £1.35m paid at Christie's in 1991 for the Paul de Lamerie, Maynard sideboard dish from the Hilmar Reksten Collection.
Speaking after the sale, Lewis Smith said: "It's a pleasing result for the silver market, it sets a new standard."
In a packed saleroom, 17 of the 21 lots of aristocratic treasures changed hands for a hammer total of £13.95m.