The Star of Sierra Leone: Shape, Size and Value

The Star of Sierra Leone: Shape, Size and Value

The Star of Sierra Leone: Shape, Size and Value

Posted by Sharif Khan on 15th Dec 2019

The Star of Sierra Leone

The diamond trade is one of the most lucrative industries. Thousands of shoppers troop to jewelry stores each day, ready to invest in their dream jewelry. But do you understand the history behind those gorgeous diamonds on store displays?

Miners work tirelessly to supply the jewelry world with raw diamonds continuously. And during their mining operations, they occasionally unearth massive diamond ores. Before such stones are sold to processing firms, we should understand the intrigues surrounding their sale and processing. You never know; that exquisite piece of an engagement ring might have been cut out of these gigantic finds. One such discovery is the Star of Sierra Leone.

What Is It?

The Star of Sierra Leone is one of the world’s largest documented diamond finds. It’s also believed to be one of the largest pieces of precious stones ever discovered. The stone was unearthed by a group of diamond miners working on the Diminco alluvial mines, on 14 th February 1972. Diminco mines are located in the Koidu region of Sierra Leone. The name Diminco is an abbreviation for Diamond Mining Company, a state-sponsored mining and exploration company in Sierra Leone.

The Star of Sierra Leone has been ranked the fourth-largest gem-quality diamond ever discovered. However, it’s still the world’s largest diamond find in alluvial mines. At the time of its discovery, the Star of Sierra Leone weighed a whopping 969.8 carats. Not only would the stone change the fortunes of the country, but there was also significant media spotlight surrounding its discovery. Besides, the Sierra Leone government took up the initiative of marketing the diamond.

On 3rd October 1972, the then Sierra Leone president, Siaka Stevens, announced a deal to sell the Star of Sierra Leone. The deal was secured with the New York City jeweler, Harry Winston, at a cost of $2.5.

But even before this, Sierra Leone wasn’t new to historical diamond finds. Two years before the discovery of the Star of Sierra Leone, the Sefadu diamond held the record as the country’s largest diamond find. The relatively huge stone weighed 620-carats.

James Allen

Quality and Appearance

Diamonds obtained in Sierra Leone have an international reputation for being some of the highest-quality gems. Such diamonds are especially lauded for their purity and clarity. Mostly, they come with minimal inclusions. That makes their processing easy and their sale lucrative. Sierra Leone diamonds are so clear, colorless, and transparent that they’re often christened “glasses”. However, it’s important to note that the diamonds that were cut from the Star of Sierra Leone are yet to be graded for clarity and color. All the same, gem experts believe they’re likely D-color diamonds, and largely flawless.

The Star of Sierra Leone is a colorless, pellucid, and lustrous crystal. As you may know, these are features that are associated with superior quality diamonds.

One of the diamond’s unique attributes is its perfect chemical purity. Chemical purity results from the absence of the common impurities that normally accompany precious stones. Examples of such impurities include boron, nitrogen, and hydrogen. Besides its chemical purity, the stone is also structurally perfect. Structural perfection is attributed to the lack of visually-perceptible plastic distortions in the crystal. Both the chemical and structural characteristics of a diamond impact its overall quality, especially with regards to its brilliance and clarity. And since the Star of Sierra Leone features no chemical or structural flaws, it scores remarkably high in  the diamond color range and clarity scale.

Due to these unique attributes, the Star of Sierra Leone ranks as a Type IIa diamond. Less than 1% of the world’s diamonds fall under this category. So, besides its exceptional quality, the Star of Sierra Leone also belongs in a league of the few.


Purchase and Processing

Harry Winston purchased the Star of Sierra Leone the same year the diamond was discovered. After acquiring the diamond, Lazare Kaplan was entrusted with the cutting process. However, the cutting process didn’t quite commence immediately.

During this time, Lazare Kaplan was among the few world-renowned diamond cutters and cleavers, having demonstrated a long history of excellence in the trade. Mr Kaplan was descended from three generations of expert diamond cutters. The earlier members of his generation had learned and perfected the art of diamond cutting and cleaving in Antwerp, Belgium. One of their most notable works was the successful cutting of Jonker in 1936. Lazare Kaplan’s experience in the trade saw him pioneer the establishment of Puerto Rico’s diamond cutting industry. He was about to bring this experience to bear in cutting the world’s largest and most famous diamond at the time.

Kaplan studied the Star of Sierra Leone carefully. As usual, his focus was more on how to bring out maximum sparkle and brilliance in the diamond. Lazare Kaplan spent the next year or so visualizing how the stone would look after cutting. And when the day for cutting arrived, the event was broadcast live on television. Therefore, the diamond isn’t only a treasured gem in Sierra Leone. It’s also quite revered in America. When the cutting process finally ended, the Sierra Leone government issued a unique commemoration stamp, marking this event. The stamp had a special feature – a diamond-like shape that was complete with a crown as well as a table and a pavilion.

Initially, the Star of Sierra Leone was cut into an  emerald-shaped stone. The new piece weighed 143.2 carats. However, the diamond had numerous significant inclusions that marred its clarity and overall rating. Therefore, it was only logical to cleave it further. Subsequent cleaving eventually reduced the stone into seventeen separate pieces. Out of these, thirteen were considered flawless. And the largest stone out of the flawless pieces was a  pear-shaped diamond weighing 53.96 carats. Harry Winston set six of the cuts from the original rough diamond into the "Star of Sierra Leone" brooch.

The Star of Sierra Leone will go down in history as the world’s most historic diamond finds. Not only that, it’s one of the diamonds who’s cutting and processing generated massive media publicity. Perhaps due to the immense economic and sentimental value that the government of Sierra Leone attached to the diamond. Cullinan, weighing in at 3,106 carats and discovered in South Africa in 1905, may still hold the record for the world’s largest diamond find. However, the Star of Sierra Leone ranks much better in terms of purity and superior quality, as is the case with most Sierra Leone diamonds.