A collection of jewellery belonging to Wallis Simpson will feature in Bonhams' September 17 Fine Jewellery auction in London.

The top lot is a diamond riviere necklace, consisting of 40 diamonds, that carries an estimate of £250,000-400,000 ($413,188-661,102).

Wallis Simpson had extravagant taste in jewellery

Simpson was known for her extravagant taste in jewellery. Last year a pair of pearl necklaces and a Cartier bracelet achieved strong results at auction.

Also featured is a diamond frog presented to Simpson in 1936 by future husband Edward Duke of Windsor shortly after he abdicated to marry the divorcee. The couple then had to remain apart for six months until Simpson's divorce was finalised.

In a letter, Edward writes: "I enclose an eanum frog for the thirty first to live in your bag with the fat Vienna frog.

"Please show the new eanum frog to HER as HE has seen it! …God bless WE my beloved Wallis. Remember what the eanum frog says and that I love you more and more..."

Bonhams reports that "'Eanum' was an invented word, part of the lovers' sentimental language, meaning 'little'".

We have this handwritten letter from Wallis Simpson, written on the couple's honeymoon in 1937.

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