The second-largest diamond ever mined was recently discovered at Lucara Diamond Corps.' Karowe Mine in Botswana. It weighs 1,111 carats, or approximately half a pound (!).
While this is quite a respectable carat weight, it's still only a fraction of the size of the current world's-largest-diamond champion, the Cullinan diamond, which was unearthed in 1905 and weighed a whopping 3,106 carats before being broken apart and made into a whole bunch of the British crown jewels.
It will be exciting to see what Lucara decides to do with their new fabulous find, which is expected to fetch between $40 and $60 million dollars.