He loathed vanity so much that he insisted his portraits depict him faithfully, 'warts and all'.

And even after his death, Oliver Cromwell's instructions were followed to the letter.

This death mask shows the puritanical Lord Protector of England in all his grizzled, lumpy glory.

There has been no attempt to conceal the growth on his lower lip or straighten his crooked nose.

All in all, the mask doesn't make an attractive artwork - though that probably won't bother the person who buys it this week.

The plaster cast, made around 350 years ago, has been put up for sale at auction by a private collector.

It has an estimated value of £1,000, even though experts cannot be sure exactly when it was made.