Insight into Madame de Pompadour, the chief mistress of Louis XV (the King of France between 1715 and 1774), and her suitably baroque sensibilities, can be gleaned from two examples of extravagant furniture that are to be sold at Christie's on December 6.

Madame de Pompadour's drop-leaf desk carries an estimate of $8m

A Louis XV ormolu-mounted Japanese lacquered bureau en pente (circa 1769) and a second, larger and similarly decorated drop-leaf desk, known in French as a "secretaire a abanttant" (circa 1756-7), are to be sold alongside several other fine, decorative items from the Riahi collection.

The smaller bureau en pente has been given an estimated sale value of £4m ($6m) by Christie's, while the exquisitely finished drop leaf desk carries a £5m ($8m) high valuation.

A part of the Riahi collection realised $64m at Christie's New York in 2000, underlining the notion that the Iranian couple are among the pre-eminent collectors of 18th century art and antiques.  

Madame de Pompadour was born Jeanne Antionette Poisson in 1721. Her formative years were steeped in scandal and rumours of illegitimacy.

After her mother's husband, Francois Poisson, fled France, his young family and mounting debts, Le Normant de Tournehem (thought to be Jeanne's true father) took over her guardianship.

Introduced to Louis XV at a masked ball in 1745, Jeanne quickly became his mistress despite facing a great deal of snobbishness at court: Madame de Pompadour was famously called "fishy" by those who believed the King was disgracing himself in cavorting with a commoner.

The pair of de Pompadour's desks are thought to be two of the finest of their kind, thus their place in the Riahi collection and substantial estimates.

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