Program Speaker - Doug Irving  on South Africa

by Nancy L. Attaway

Paul Hlava introduced Doug Irving as the scheduled speaker for tonight. Doug described his trip to southwest Africa (Namibia) and South Africa that he made some years ago. Before he began talking about Africa, however, Doug provided an update on Canadian diamonds. He remarked that three million carats were being produced per year from the Ekati mine, and that a Canadian diamond cutting factory has been established. He also mentioned that the Canadian government was objecting to the logo inscribed on Canadian diamonds, which the government thinks too closely resembles the official Canadian logo.

Doug Irving began by saying that South Africa is home to significant deposits of gold and diamonds. Gold ore is found near Johannesburg. The famous Premier diamond mine lies northeast of Kimberley and east of Pretoria. The diamond-rich ore of the Premier mine is kimberlite. The Premier mine was discovered by Thomas Cullinan in 1902.

Doug said that the beach sands of Namibia’s west coast contain alluvial deposits of very fine quality diamonds. The diamonds found on the coast of Namibia have been weathered from inland deposits, from kimberlites in the interior of South Africa, and have traveled downstream. The lesser quality diamonds have been broken from the action of the tumbling water. The best quality diamonds remain intact. A railroad worker first found diamonds in the sand dunes near Kolmanskop, Namibia in 1908. Although there are kimberlites in Namibia, they do not contain diamonds.

Many of South Africa’s game parks and wildlife preserves are located mainly in the north and eastern sections, surrounded by tall grass savannas. Doug said that visitors stay overnight in rondavels, round structures that serve as motels. The parks and preserves are closed from dusk until dawn to protect visitors from wild animals. Many place names in South Africa reflect a strong German influence.

The famous Kalahari Desert lies north of South Africa and east of Namibia. The Tropic of Capricorn runs a horizontal line across the central part of Namibia, the southern part of Botswana, the northern part of South Africa, and the southern part of Mozambique. South of the Kalahari Desert and also between the Kalahari Desert and Namibia lies a vast region of desert shrub. Very little vegetation grows along the west coast of Namibia.

Tsumeb lies in the north-central part of Namibia and is home to many world famous mineral specimens, such as the magnificent examples of the rich green and blue-green hexagonal crystals of dioptase. Ore from the copper, lead, zinc, and silver mines there all showed high concentrations of arsenic. Doug remarked that over two hundred different minerals were unearthed from the mines, however, they are all now closed. When Doug visited the area, he noticed that the drivers of the tour buses were actually armed commandos. Doug mentioned that airplanes had to fly at an altitude of 18,000 feet to avoid getting shot down by missiles.

Doug showed slides of Aranda, a large uranium mine, where 170 tons per load by truck is mined. The work force lives nearby, and mineworkers have access to great medical and educational facilities. Doug also discussed the Ornetis mine, an underground copper and silver mine. He remarked that the region which encompasses Namibia’s mining area receives less than one inch of rain per year, where 300-foot high sand dunes and 1,000 year old plants may be found.

Doug also visited the Namibian coastline, where diamonds were first dredged in 1965. Massive sea walls hold back the ocean during the mining of diamond-bearing terraces in the foreshore to depths of 66 feet below sea level. An offshore dike was built to mine the gravel. Doug explained that diamonds are found between the gravel and the bedrock. He noticed that workers swept diamonds by hand and labored in an area that was entirely cordoned off from visitors. This area was very heavily guarded. The workers usually stay six to nine months at a time.

Doug described how mechanized shape-sorters for diamonds at the mines in Namibia turned 3,000 cycles per second. Sorting was done by hand to separate diamonds from the concentrate. Most diamonds found there are colorless, but some colored diamonds are found. As many as 3,000 carats of diamonds are mined per day. Doug mentioned that the mine managers must keep the different tribes separated or fights will occur. Some of the cultures are very different, and some of the tribes remain old enemies to this day.

Doug was interested in the mining history and visited some of the mining museums. Some of these museums displayed the old machinery used in the early days of mining.

Doug described one of the underground gold mines that descended nearly 8,000 feet into the earth. Doug said that underground gold mines are very labor intensive. Gold is poured into bars that weigh 1,000 ounces. Gold bars are then stacked on wooden frames known as wood packs. Under the tremendous weight of the gold, the wood is slowly squeezed until it all settles. Metal frames are not used, as they would be too brittle and would break. One gold mine now goes down to 12,000 feet, and there are plans to go down to 15,000 feet. Doug said that gold was formed in ancient placers that were washed downstream.
Doug visited Pretoria, the legislative capital of South Africa. Pretoria lies north of Johannesburg. He visited a mining operation where carbonate, copper, phosphate, magnetite, gold, and silver were all mined. Doug went to Barberton, northwest of Swaziland, to visit gold mines in that area, where 30 tons of gold have been extracted.

Doug described Capetown as an old and very picturesque colonial city. He said that Table Mountain, the famous geologic feature of Capetown, is an old sandstone. The southern region of South Africa along the coast is a very mountainous. Capetown is located at the tip of South Africa. The area receives enough rainfall to sustain a Mediterranean-like vegetation. Several vineyards grow varieties of fine white vines. Doug visited the Shellanvosch Vineyards and sampled some of their product.

Doug stated that a special permit, issued by both the mine and the government, is required to convey gold out of South Africa. The world demand for gold now runs 3,500 tons per year, or one hundred million ounces. In the US, 27,000 tons of gold are housed in Ft. Knox. Most of the demand for gold is industrial, as used in computer circuits.

Doug announced that a new lease has been issued in Tsumeb to explore the upper reaches of the mine for more of the fabulous dioptase specimens. He remarked that many fine specimens were destroyed just to obtain whatever copper had been present in the specimen. Some of these specimens were truly magnificent and measured three feet tall.

Thank you, Doug for sharing your South African tour!