Largest Clear Diamond:-
Cullinan diamond, world's largest gem diamond, which weighed about 3,106 carats in rough form when found in 1905 at the Premier mine in Transvaal, S.Af. Named for Sir Thomas Cullinan, who had discovered the mine three years earlier, the colorless stone was purchased by the Transvaal government and was presented (1907) to the reigning British monarch, King Edward VII. It was cut into 9 large stones and about 100 smaller ones by I.J. Asscher and Company of Amsterdam.
The largest polished gem from the stone is named Cullinan I or the Great Star of Africa and at 530.2 carats (106.04 g) was the largest polished diamond in the world until the 1985 discovery of the Golden Jubilee diamond (545.67 cts), also from the Premier mine. (Golden Jubilee is a brown diamond)
Cullinan I is now mounted in the head of the Sceptre with the Cross. The second largest gem from the Cullinan stone, Cullinan II or the Lesser Star of Africa, at 317.4 carats (63.48 g), is the third largest polished diamond in the world and is also part of the British crown jewels, as it forms a part of the Imperial State Crown. Both gems are on display at the Tower of London, as parts of the British crown jewels.