Letseng diamond mine
| Location | |
|---|---|
  Letseng diamond mine | |
| Country | Lesotho |
| Coordinates | 29°0′01″S 28°51′43″E / 29.00028°S 28.86194°ECoordinates: 29°0′01″S 28°51′43″E / 29.00028°S 28.86194°E |
| Production | |
| Products | diamonds |
| Type | diamond |
The Letseng diamond mine, found in the landlocked Southern African kingdom of Lesotho, is owned by Gem Diamonds, Ltd. and the government of Lesotho, and at an elevation of 3,100 m (10,000 ft) it is the world's highest diamond mine.
Production
It is characterised by extremely low grade ore (less than 2 carats (400 mg)/hundred tons) and is well known for producing huge diamonds, having the highest percentage of large diamonds (greater than 10 carats (2.0 g)), giving it the highest dollar value per carat of any diamond mine. The world average is roughly US$81 per carat, while Letseng averaged over US$1,894 per carat for the first six months of 2007.[1]
Unusual for Africa, and due to the elevation, temperatures at the mine drop to -20 °C, and snowfalls are common in winter.
Geography
Climate
Letseng has a tundra climate (ET, according to the Köppen climate classification), with an average annual precipitation of 881 mm (35 in). This climate has chilly to cold temperatures throughout the year, with snowfalls.
| Climate data for Letseng-la-Terae | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Year |
| Average high °C (°F) | 14.8 (58.6) |
14.5 (58.1) |
12.2 (54) |
10.6 (51.1) |
7.7 (45.9) |
5.4 (41.7) |
5.4 (41.7) |
6.8 (44.2) |
9.9 (49.8) |
11.2 (52.2) |
12.6 (54.7) |
13.7 (56.7) |
10.4 (50.73) |
| Daily mean °C (°F) | 9.8 (49.6) |
9.7 (49.5) |
7.7 (45.9) |
5.1 (41.2) |
2.0 (35.6) |
−0.1 (31.8) |
0.0 (32) |
1.5 (34.7) |
4.6 (40.3) |
6.0 (42.8) |
7.5 (45.5) |
8.9 (48) |
5.23 (41.41) |
| Average low °C (°F) | 4.8 (40.6) |
4.9 (40.8) |
3.3 (37.9) |
−0.3 (31.5) |
−3.6 (25.5) |
−5.5 (22.1) |
−5.3 (22.5) |
−3.8 (25.2) |
−0.6 (30.9) |
0.8 (33.4) |
2.5 (36.5) |
4.1 (39.4) |
0.11 (32.19) |
| Average precipitation mm (inches) | 133 (5.24) |
119 (4.69) |
120 (4.72) |
67 (2.64) |
20 (0.79) |
10 (0.39) |
8 (0.31) |
24 (0.94) |
57 (2.24) |
89 (3.5) |
115 (4.53) |
119 (4.69) |
881 (34.68) |
| Source: Climate-data.org[2] | |||||||||||||
Significant diamond finds
Lesotho Promise
On the 4th of October 2006 the 603 carat (121 g) white diamond, the Lesotho Promise was unearthed, and is the largest reported find this century and the 15th largest diamond ever found. The stone is an exceptional colour, rated D, the top colour for diamonds.
Lesotho Brown
Previously the largest diamond found at Letseng was the 601 carat (120 g) Lesotho Brown, recovered in 1967.
Letseng Legacy (September 2007)
On September 13, 2007 Gem Diamonds, Ltd. announced that it found a 493 carats (98.6 g) diamond, making it the 18th largest diamond ever found. It was sold to the Graff-SAFDICO partnership for $10 million.[1]
Star of Lesotho
In 2004, Gem Diamonds, Ltd. found a large diamond of 123 carats (24.6 g).[3]
Leseli La Letšeng (September 2008)
On September 21, 2008 Gem Diamonds, Ltd. announced that it found a 478 carats (95.6 g) diamond of high quality, making it the 20th largest diamond ever found. It is a type II D colour, with potential to yield a 150 carats (30 g) cut stone. Chief executive Clifford Elphick said: "Preliminary examination of this remarkable diamond indicates it will yield a record-breaking polished stone of the very best colour and clarity, and has no inclusions visible in its rough form."[4][5] [6]
November 2010
The discovery of two large rough white diamonds was announced in November 2010.[7] They weighed 196ct and 184ct.[8]
See also
References
- 1 2 "Big diamond discovery in Africa". Finance 24. Fin24.com. 2007-09-13. Retrieved 13 September 2007.
- ↑ "Climate: Letseng-la-Terae". Retrieved 26 April 2015.
- ↑ "Star of Lesotho". Retrieved 14 April 2008.
- ↑ menafn.com, World's 20th largest rough diamond found in Lesotho
- ↑ news.bbc.co.uk, Massive diamond found in Lesotho
- ↑ "Lesotho mine yields one of world's largest diamonds". Retrieved 21 September 2008.
- ↑ "Mining Journal - Gem recovers another large diamond from Letseng". Retrieved 2010-11-10.
- ↑ "Mining Journal - Gem sells diamonds for US$22.7 million". Retrieved 2010-11-28.