Discovered in a pile of rubble in the in the Democratic Republic of Congo in 1984, the 890 carat (rough) was eventually cut into a 407.5 carat Fancy brownish yellow stone with fourteen additional satellite stones of varying colors, from near-colorless to rich yellow-brown. Graded by the GIA in 1988 as internally flawless, the stone is thought to still be in the possession of one of its original owners, Louis Glick (who had bought the stone together with Donald Zale and Marvin Samuels).
The dimoand rough was discovered in the rubble from a diamond mine by a young girl who was playing outside her uncle's house. The uncle sold the diamond to some local African diamond dealers who sold it to some Lebanese diamond dealers for an undisclosed amount, and they sold it to a senior De Beers buyer. De Beers sold the stone to Donald Zale.
Supervision of the cutting was given to Mr. Samuels as this was his expertise. The Incomparable required all of Samuels’ experience as its basic shape was extremely irregular - thicker at one end, narrower at the other; sunken and pitted on one side, ridged on the other. Once the stone had been initially polished though and the interior opened up, it was virtually free of inclusions.