"Carrying a large box, Mrs Malik appears at the top of the stairs. 'I hope your Mama will adore the thread. It cost near a King's ransom'.
Nice to hear the cliché is alive and well here. On second thoughts, maybe it is just colloquial here?"

This may be a cliché, but let me tell you something, I have spent a very long time trying to track down the origin of this phrase. Some people believe that it can be traced back to Richard I of England, also known as Richard the Lionheart, when he was captured in 1192. Around 500 years before the setting of The Dresskeeper. This is one where you will need to pay attention.

Richard the Lionheart had spent some time fighting the Third Crusade (for more information on The Crusades go to your local library, how many times have you visited that dusty old building in the last year?).

On his way back he was hit by terrible weather and had to find a new route to return home to England. He ended up in Austria, land of Duke Leopold V. He had problems with Leopold during the Crusade because Richard had asked his men to tear down Leopold's flag and throw it into the moat surrounding Acre, Northern Israel, where they had been fighting. The angry Duke left shortly afterwards.

When in Austria he was captured by Leopold. Germany paid 75,000 marks to keep King Richard in their custody.

Now this is the important bit...
News had spread that the King had been captured and a ransom was demanded for the Kings return. Even his mother, Eleanor of Aquitaine, had contacted the Pope for help. The people of England had been taxed to the limit for the return of their King who was never present to rule over them in the first place - he had gone off to fight. The price of the king had risen to 150,000 marks, which accoring to this website, amounted to three years of annual income and weighing at three tons in silver.

And finally...
Do you know the legend of Robin Hood? While King Richard was away, his brother Prince John had been scheming to take the throne away from him and was unofficially ruling the land while his brother was in captivity. According to legend, Robin Hood was trying to uphold justice in the name of the real King during this time.