The story goes that when the diamond was split, the knife broke during the first attempt. "The tale is told of Joseph Asscher, the greatest cleaver of the day," wrote Matthew Hart in his book Diamond: A Journey to the Heart of an Obsession, "that when he prepared to cleave the largest diamond ever known, the 3,106 carats (621 g) Cullinan, he had a doctor and nurse standing by and when he finally struck the diamond and it broke perfectly in two, he fainted dead away."
Rumours abound of a "second half" of the Cullinan diamond. According to Sir William Crookes the original, uncut diamond was itself "a fragment, probably less than half, of a distorted octahedral crystal; the other portions still await discovery by some fortunate miner. Crookes thus indirectly indicates that the original, larger crystal broke in a natural way and not by a man-made cut. Others[who?] have speculated that before Frederick Wells sold the diamond to Sir Thomas Cullinan he broke off a piece which sized in at about 1,500 carats (300 g) to 2,000 carats (400 g).