Star of Sierra Leone
Encyclopedia
The 968.9 carats Star of Sierra Leone diamond
was discovered by miners
on February 14, 1972 in the Diminco alluvial mines in the Koidu area of Sierra Leone
. It ranks as the third-largest gem-quality diamond and the largest alluvial diamond ever discovered.
On October 3, 1972, Sierra Leone's then-President, Siaka Stevens
, announced that Harry Winston
, the New York City jeweller, had purchased the Star of Sierra Leone for under $2.5 million.
The stone was initially cut into an emerald shaped stone weighing 143.2 carats (28.6 g) but was later re-cut due to an internal flaw, eventually resulting in 17 separate finished diamonds, of which 13 were deemed to be flawless. The largest single finished stone was a flawless pear-shaped diamond of 53.96 carats (10.8 g). Six of the diamonds cut from the original rough were later set by Harry Winston
into the "Star of Sierra Leone" brooch.
A rare characteristic of the stone is its perfect chemical purity: it is ranked as a type IIa diamond, a category which includes less than 1% of all diamonds.
Diamond
In mineralogy, diamond is an allotrope of carbon, where the carbon atoms are arranged in a variation of the face-centered cubic crystal structure called a diamond lattice. Diamond is less stable than graphite, but the conversion rate from diamond to graphite is negligible at ambient conditions...
was discovered by miners
Mining in Sierra Leone
The mining industry of Sierra Leone accounted for 4.5 percent of the country's GDP in 2007 and minerals made up 79 percent of total export revenue with diamonds accounting for 46 percent of export revenue in 2008...
on February 14, 1972 in the Diminco alluvial mines in the Koidu area of Sierra Leone
Sierra Leone
Sierra Leone , officially the Republic of Sierra Leone, is a country in West Africa. It is bordered by Guinea to the north and east, Liberia to the southeast, and the Atlantic Ocean to the west and southwest. Sierra Leone covers a total area of and has an estimated population between 5.4 and 6.4...
. It ranks as the third-largest gem-quality diamond and the largest alluvial diamond ever discovered.
On October 3, 1972, Sierra Leone's then-President, Siaka Stevens
Siaka Stevens
Siaka Probyn Stevens was the 3rd prime minister of Sierra Leone from 1967–1971 and the 1st president of Sierra Leone from 1971–1985. Stevens is generally criticised for dictatorial methods of government in which many of his political opponents were executed, as well as for mismanaging...
, announced that Harry Winston
Harry Winston
Harry Winston was an American jeweler. He donated the Hope Diamond to the Smithsonian Institution in 1958 after owning it for a decade, and traded the Portuguese Diamond to the Smithsonian in 1963.-History:...
, the New York City jeweller, had purchased the Star of Sierra Leone for under $2.5 million.
The stone was initially cut into an emerald shaped stone weighing 143.2 carats (28.6 g) but was later re-cut due to an internal flaw, eventually resulting in 17 separate finished diamonds, of which 13 were deemed to be flawless. The largest single finished stone was a flawless pear-shaped diamond of 53.96 carats (10.8 g). Six of the diamonds cut from the original rough were later set by Harry Winston
Harry Winston
Harry Winston was an American jeweler. He donated the Hope Diamond to the Smithsonian Institution in 1958 after owning it for a decade, and traded the Portuguese Diamond to the Smithsonian in 1963.-History:...
into the "Star of Sierra Leone" brooch.
A rare characteristic of the stone is its perfect chemical purity: it is ranked as a type IIa diamond, a category which includes less than 1% of all diamonds.