Slang for a diamond that is proper shit and not real in any way. Fake bling. More cubic zirconia than H Samuel's. Be a bonafide iced-out playa for only £9.99! Keeping it real. Cheap.
Look at David Peckham over there. It's the end of the month. Tesco's has just paid him. So he's flashing his fivers. Buying bottles fizzy wine. And he's covered head to toe in blud diamonds.
A blood diamond is a Gruffnugget pulled from the ass of a black man. However this gruffnugget will also usually include a small portion of blood to it, thus dubbed a 'Blood Diamond'.