The stone, recovered from the alluvial mining block six, was the 11th diamond of more than 100ct recovered from Lulo to date and the third for 2018.
It will be added to the inventory of large diamonds being held for sale at a later date.
Lucapa and its partners, Empresa Nacional de Diamantes and Rosas & Petalas, sold US$5 million worth of diamonds during the June quarter at an average price of $1,479 per carat.
Special stones were withheld from the sale, leaving an inventory of 2,755ct at the end of June.
