Kate Middleton's dress cost just 30 pounds

The dress worn by the future British queen, Kate Middleton, in a university fashion show which sold at auction last week for £78,000 originally cost just £30 to make.

The see-through wool outfit was designed as a skirt by fashion student Charlotte Todd, who revealed the skimpy outfit only took two days to make but admitted Kate's decision to wear it as a dress was a smart move.

She explained to the Daily Star: "I'm not sure it would have had such an impact on William if Kate had worn it as I intended."

Kate wore the dress while taking part in a charity fashion show at St Andrew's University, Scotland, and it is believed that is when Prince William - who will marry the former junior fashion buyer on April 29 - decided to take their relationship to a romantic level.

The dress raised seven times the estimated price at the Passion for Fashion event in Central London, with the winning bidder Nicky Roberts promising it will be sold again to raise money for charity.

He said: "We are going to put it in the British Antiques Dealers Association fair next week in London at the Duke of York barracks.

A gown worn by the prince's late mother Princess Diana on a state visit to France sold for £30,000 at the sale, while a Louis Vuitton vanity case owned by the Duchess of Windsor made £48,000.