Why Botswana keeps unearthing the world's biggest diamonds

Why Botswana keeps unearthing the world's biggest diamonds
24 Aug 2024

A 2,492-carat diamond—the second largest in the world—was recently unearthed in Botswana.

The Canadian mining company that found the stone, Lucara Diamond Corp., said in a statement that the diamond was discovered using X-ray equipment at the Karowe Diamond Mine in northern Botswana.

Lucara did not give a value for the find, but the Financial Times newspaper reported that people close to Lucara estimated that the stone could be worth up to $40 million (£30.6m).

Botswana's diamond boom and global standing
Diamond dominance

Botswana is one of the world's major diamond producers, and diamonds are its primary source of wealth, accounting for 30% of its GDP and 80% of its exports.

The country's first significant discovery occurred in 1967, a year after its independence, with the unearthing of the Orapa kimberlite field.

This marked the beginning of a diamond boom that led to the establishment of major mines such as Letlhakane (1968), Jwaneng (1973), Gope (1981), and Lerala (1991).

Botswana's diamond reserves and future prospects

Since then, Botswana has become the second-largest producer of natural diamonds globally, trailing only Russia.

Botswana has produced 665 million carats of diamonds since 1971, representing 14% of the world's total diamond production.

Between 1870 and 2012, the world produced approximately 4,898 million carats of diamonds, with Botswana contributing 665 million carats to this total.

The 3,106-carat Cullinan diamond, found in South Africa in 1905, is the largest gem-quality rough diamond ever found.

Advanced technology and significant diamond discoveries
Technological triumph

The Karowe Mine, where the 2,492-carat diamond was found, has produced four other diamonds over 1,000 carats in the last decade.

Before this discovery, the Sewelo diamond, also found at the Karowe Mine in 2019, was recognized as the world's second-biggest mined diamond at 1,758 carat.

The 1,111-carat Lesedi La Rona diamond, also from the same mine, was bought by a British jeweler for $53 million in 2017.

The Constellation, another diamond from Karowe, was sold for $63 million.

Mines in Botswana are located on kimberlite pipes
Market influence

All of the mines in Botswana are located on kimberlite pipes, a rare type of volcanic rock formation.

In this case, kimberlite formed approximately 90 million years ago when plumes of magma from deep inside the mantle raced upward during volcanic eruptions.

As magma passed through an area about 150 kilometers below the surface, where pressure and temperature conditions are ideal for diamond formation, it ripped off chunks of diamond-containing rock and deposited them near the surface.