Hunt A Diamond

Now here's a treasure hunt for our beleaguered times: there's a £5k diamond about to be hidden somewhere in the Square Mile - if you find it, you can keep it. The location will be revealed through four weeks (that's four weeks) of quiz questions about Leadenhall Market and the surrounding area, with the odd cryptic teaser thrown in for fun. To play, all you have to do is register your email address - it's free - by 15th May. So sharpen up your brain if you want to win this one carat sparkler. (Image / Massimo Usai)