Asbestos Mountains
Encyclopedia
The Asbestos Mountains is a range of hills in the Northern Cape
Northern Cape
The Northern Cape is the largest and most sparsely populated province of South Africa. It was created in 1994 when the Cape Province was split up. Its capital is Kimberley. It includes the Kalahari Gemsbok National Park, part of an international park shared with Botswana...

 province of South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...

, stretching SSW from Kuruman
Kuruman
Kuruman is a town with 12,701 inhabitants in Northern Cape province of South Africa, famous for its scenic beauty and the Eye of Kuruman, a geological feature bringing water from deep underground to the surface in the Kalahari Desert....

, where the range is known as the Kuruman Hills, to Prieska. The range lies about 150 km west of Kimberley
Kimberley, Northern Cape
Kimberley is a city in South Africa, and the capital of the Northern Cape. It is located near the confluence of the Vaal and Orange Rivers. The town has considerable historical significance due its diamond mining past and siege during the Second Boer War...

 and rises from the Ghaap Plateau.

The mountains were named for the asbestos
Asbestos
Asbestos is a set of six naturally occurring silicate minerals used commercially for their desirable physical properties. They all have in common their eponymous, asbestiform habit: long, thin fibrous crystals...

 which was mined in the 1900s and is found as a variety of amphibole
Amphibole
Amphibole is the name of an important group of generally dark-colored rock-forming inosilicate minerals, composed of double chain tetrahedra, linked at the vertices and generally containing ions of iron and/or magnesium in their structures.-Mineralogy:...

 called crocidolite. Veins occur in slaty rocks, and are associated with jaspers
Jaspers
Jaspers can refer to* Dick Jaspers , a Dutch professional carom billiards* Karl Jaspers, German psychiatrist and philosopher* Jason Jaspers , a professional ice hockey centre from Canada...

 and quartzites rich in magnetite
Magnetite
Magnetite is a ferrimagnetic mineral with chemical formula Fe3O4, one of several iron oxides and a member of the spinel group. The chemical IUPAC name is iron oxide and the common chemical name is ferrous-ferric oxide. The formula for magnetite may also be written as FeO·Fe2O3, which is one part...

 and brown iron-ore. Geologically it belongs to the Griquatown
Griquatown
Griekwastad is a country town in South Africa. It is sometimes still called Griquatown, a name which is now considered historical. The town is situated in the Northern Cape Province of South Africa about from the city of Kimberley...

 series.

The Griquas, for whom Griquatown was named, were a Khoikhoi
Khoikhoi
The Khoikhoi or Khoi, in standardised Khoekhoe/Nama orthography spelled Khoekhoe, are a historical division of the Khoisan ethnic group, the native people of southwestern Africa, closely related to the Bushmen . They had lived in southern Africa since the 5th century AD...

 people who in 1800 were led by a freed slave, Adam Kok, from Piketberg
Piketberg
Piketberg is a town in the Western Cape, South Africa. The original spelling of the name was "Piquetberg".The town is in the foothills of the Piketberg mountains, a range of low mountains formed from Table Mountain Sandstone....

 in the western Cape
Western Cape
The Western Cape is a province in the south west of South Africa. The capital is Cape Town. Prior to 1994, the region that now forms the Western Cape was part of the much larger Cape Province...

 to the foothills of the Asbestos Mountains where they settled at a place called Klaarwater. John Campbell
John Campbell (missionary)
John Campbell , was a Scottish missionary and traveller.He attended the Royal High School and was at one time apprenticed to a goldsmith. Campbell helped found the Magdalene Society, a Religious Tract Society of Scotland in 1793, and the Missionary Magazine in Edinburgh in 1796...

, (1766–1840), a Scottish missionary in South Africa, renamed it Griquatown in 1813. The mission station became a staging post for expeditions to the interior - here David Livingstone
David Livingstone
David Livingstone was a Scottish Congregationalist pioneer medical missionary with the London Missionary Society and an explorer in Africa. His meeting with H. M. Stanley gave rise to the popular quotation, "Dr...

 met his future wife, Mary Moffat, daughter of the missionary Robert Moffat
Robert Moffat
Robert Moffat was a Scottish Congregationalist missionary to Africa, and father in law of David Livingstone....

 - William Burchell visited here in 1811.

John Campbell described the mountains in his book "Travels in South Africa: Undertaken at the request of the Missionary Society":

The colour variants which Campbell found, are named, because of their chatoyance, "Tiger's Eye", "Hawk's Eye", and "Cat's Eye" by lapidaries
Lapidary
A lapidary is an artist or artisan who forms stone, mineral, gemstones, and other suitably durable materials into decorative items such as engraved gems, including cameos, or cabochons, and faceted designs...

 and are silicified crocidolite.

Wonderwerk Cave
Wonderwerk Cave
Wonderwerk Cave is an archaeological site, formed originally as an ancient solution cavity in Dolomite rocks of the Kuruman Hills, situated between Danielskuil and Kuruman in the Northern Cape Province, South Africa. It is a National Heritage Site within a servitude ceded to and managed as a...

 is located in the range near Kuruman and was occupied by man during the Later Stone Age, while much earlier manuport
Manuport
In archaeology and anthropology, a manuport is a natural object which has been moved from its original context by human agency but otherwise remains unmodified. The word derives from the Latin words manus, meaning 'hand' and portare, meaning 'to carry'.Examples include stones or shells moved from...

s, introduced by hominins in the terminal Acheulean
Acheulean
Acheulean is the name given to an archaeological industry of stone tool manufacture associated with early humans during the Lower Palaeolithic era across Africa and much of West Asia, South Asia and Europe. Acheulean tools are typically found with Homo erectus remains...

, have been found at the back of the cave.

Mining history

Serious mining of crocidolite in these mountains started in 1893 when open-cast quarrying produced 100 tons of material. By 1918 underground mining had started and scattered mines were to be found from Prieska to Kuruman along the length of the range, and mills were constructed at both of these towns. Between 1950 and 1960 production had risen to 100 000 tons, each mine was doing its own milling and the tailings dumps had grown in size.

Health hazards

At the time of Campbell's writing the health hazards of asbestos were unknown. Tens of thousands of mineworkers were exposed to the fibres at their workplaces, and when winds blew across the wastedumps, at their homes. By the mid 1950s the medical profession were still diagnosing asbestosis as "metastatic carcinomas from an unknown primary site". The resulting increase in cases of asbestosis
Asbestosis
Asbestosis is a chronic inflammatory and fibrotic medical condition affecting the parenchymal tissue of the lungs caused by the inhalation and retention of asbestos fibers...

 and mesothelioma
Mesothelioma
Mesothelioma, more precisely malignant mesothelioma, is a rare form of cancer that develops from the protective lining that covers many of the body's internal organs, the mesothelium...

 became alarming. Records later revealed that pleural endothelioma had first been reported in 1917, but had also been considered as metastatic.
Substitutes for asbestos now include ceramic, carbon, metallic and Aramid
Aramid
Aramid fibers are a class of heat-resistant and strong synthetic fibers. They are used in aerospace and military applications, for ballistic rated body armor fabric and ballistic composites, in bicycle tires, and as an asbestos substitute. The name is a portmanteau of "aromatic polyamide"...

 fibers, such as Twaron
Twaron
Twaron is the brandname of Teijin Aramid for a para-aramid. It is a heat-resistant and strong synthetic fibre developed in the early 1970s by the Dutch company AKZO, division Enka, later Akzo Industrial Fibers. The research name of the para-aramid fibre was originally Fiber X, but it was soon...

 or Kevlar
Kevlar
Kevlar is the registered trademark for a para-aramid synthetic fiber, related to other aramids such as Nomex and Technora. Developed at DuPont in 1965, this high strength material was first commercially used in the early 1970s as a replacement for steel in racing tires...

.

David Goldblatt from the University of the Witwatersrand
University of the Witwatersrand
The University of the Witwatersrand, Johannesburg is a South African university situated in the northern areas of central Johannesburg. It is more commonly known as Wits University...

 wrote:


A similar situation had arisen in the 1920s in the United States with the careless handling of radium and the ensuing scandal of the Radium Girls
Radium Girls
The Radium Girls were female factory workers who contracted radiation poisoning from painting watch dials with glow-in-the-dark paint at the United States Radium factory in Orange, New Jersey around 1917....

.

The Green Mountains
Green Mountains
The Green Mountains are a mountain range in the U.S. state of Vermont. The range extends approximately .-Peaks:The most notable mountains in the range include:*Mount Mansfield, , the highest point in Vermont*Killington Peak, *Mount Ellen,...

, for which Vermont
Vermont
Vermont is a state in the New England region of the northeastern United States of America. The state ranks 43rd in land area, , and 45th in total area. Its population according to the 2010 census, 630,337, is the second smallest in the country, larger only than Wyoming. It is the only New England...

 was named, were produced by the same geologic processes that produced the Asbestos Mountains - they produced an abundance of serpentine, which is the source of chrysotile asbestos.
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