A 1663 Charles II patterned silver "Reddite" crown is the headline lot of Spink's March 26-27 sale in London with a £100,000-120,000 ($167,650-201,180) estimate.
The coin was designed by Thomas Simon (1623-1665) - the most important engraver of his era - and is considered his magnum opus.
It is named for the inscription that encircles the edge, "Reddite quae Caesaris Caesari &ct post" or "Render unto Caesar the things which are Caesar's". The coin celebrates the restoration of the Crown following the brief Cromwellian reign.
Another set of coins known as the "Petition" crowns were struck from the same dies, featuring a message from Simon to Charles II (1630-1685) that reads: "thomas simon most hvmbly prays yovr majesty to compare this his tryall piece with the dvtch and if more trvly drawn & emboss'd more grace: fvlly order'd and more accvrately engraven to releive him."
In 2007, a Petition crown set a new auction record at Spink, achieving £207,000 ($347,035).
It seems likely that this coin will exceed the record, as the silver Reddite version is significantly rarer than the Petition, with only five surviving specimens.
Only 30 examples of the crown in all materials and variations are known to exist.
The coin features a bust of the king based on a miniature by Samuel Cooper (1609-1672), with the royal coat of arms encircling a cross of St George on the reverse.
We have a range of rare coins available to purchase, including this lightweight gold Unite coin issued in 1626 under the reign of Charles I (1600-1649).
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