On 17th September, the autumn Fine Jewellery sale takes place at Bonhams newly built headquarters on London's New Bond Street.                           

A diamond frog which was a gift from The Duke of Windsor to his lover Wallis Simpson is offered together with a diamond brooch designed as the Prince of Wales' feathers. The two items are estimated to sell for £5,000-£10,000. The diamond and green peridot frog dates from 1937 - the year of Edward's abdication. 

During an enforced separation after the abdication and before their marriage, The Duke wrote to Wallis: "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..." ("Eanum" was an invented word, part of the lovers' sentimental language, meaning "little"). 

The most valuable jewel in the sale is a spectacular diamond rivière necklace, estimated at £250,000-£400,000 and composed of 40 brilliant-cut sparkling diamonds. The rivière style, meaning literally 'river' in French, has a timeless elegance; the stream of diamonds increase in size towards the largest central stone. The diamonds weigh 76 carats in total. 

Seventy-five pearls, fastened with a diamond clasp, make up the second most valuable lot in the sale - a single-strand natural saltwater pearl necklace dating from c.1910. It is offered with an estimate of £150,000-£200,000. 

A sapphire and diamond 'pelouse' - or 'lawn' - suite by Van Cleef and Arpels is estimated to sell for £80,000-£100,000. A choker and bracelet are fashioned as a 'lawn' of circular-cut sapphires, interspersed with diagonal rows of diamonds. A ring and earclips complete the set in a matching sapphire and diamond bombé design.  

Another piece of historical interest is a pearl brooch that belonged to Nancy Astor. The natural saltwater pearl drops are decorated with rose-cut diamonds and mounted in gold. The brooch is offered with an estimate of £12,000-£15,000. Nancy, Viscountess Astor (1879-1964), was famous as a society hostess and as the first woman to sit as a Member of Parliament when she succeeded her husband, Waldorf Astor, to win his former seat. Lady Astor liked to welcome her guests by posing at the top of a staircase, sparkling with jewels.

For more info, go to www.bonhams.com