Last week we asked: 

This original 1632 Second Folio of Shakespeare's works (below) auctioned last month at PBA Galleries. Missing 17 leaves, with some minor occasional staining, what price did it make?

$7,000, $25,000, $65,000 or $90,000?

Shakespeare's Second Folio - not so rare

The correct answer was $25,000. Congratulations if you're among the 8% who got it right.

Doesn't $25,000 seem on the cheap side for an early Shakespeare folio? That's largely down to its relative ubiquity.

In fact third folios (from 1663) are rarer than the second offering, and more valuable. That's because many of the unsold editions of the third folio were destroyed in the Great Fire of London in 1666. One third folio sold for $374,500 in 2012.

First folios are, however, what every Shakespeare collector wants. Around 230 survive, and have achieved up to $6.1m in the past.

This week: