Ottosdal, North West
Encyclopedia
Ottosdal is a small town
which had a population of 1,274 in 1985. It is situated at an altitude of 1,479 meters (4,855 feet), on the branch railway line from Makwassie in the central North West Province of South Africa
. Main routes to and from major population and economic centers, i.e. Pretoria
, Johannesburg
and Vereeniging, to Namibia
and Botswana
pass through it. Ottosdal is a farming community engaged in the growing of grains such as mealies, sunflower
and monkeynuts. In addition, local farmers raise cattle, sheep, pigs, dairy cows and chicken. A major pyrophyllite
mine lies near it on the farm Gestoptefontein. This town originated from the establishment of a Dutch Reformed Church
parish in 1913. To this was added a church building on Korannafontein, the farm of Gerhardus Petrus Otto. Ottosdal grew around the church and was officially registered in 1917 and named after G. P. Otto (de Jager 1997).
mines located on the farm Gestoptefontein. These mines produce a very high quality pyrophyllite, which is a phyllosilicate
mineral
composed of aluminium
silicate
hydroxide
: AlSi2O5OH. The pyrophyllite is a metamorphosed
clay
. The clay was formed by the alteration of volcanic ash
, which apparently accumulated at the bottom of a quiet body of water. It forms a dense, but soft light grey, or darker, fine-grained stone, which splits into well-defined slabs. The strata
, in which it occurs, is a 3.0 to 3.1 billion year-old, over 2 kilometer-thick assemblage of arenaceous sediments, conglomerates
, grits, basic volcanics, tuff
s, coarse pyroclastic rocks and quartzite
called the "Dominion Group".
Originally, pyrophyllite
was quarried and locally used for tombstones and building stone and to carve ornaments and utensils such as pots, dishes and cases. Currently, it is milled and processed near where it is mined to produce material used for the production of a wide variety of products. They include acid-resistant lab ceramics, refractory bricks and linings, filler in paint, electrical insulation, boilermaker's chalk, chromic-acid purification pots, and crucibles used in the manufacture polycrystalline-diamonds. Blocks of pyrophyllite are stilled quarried and sold as either "Wonderstone" or "African Stone" for sculpting. It can be easily carved with rasps and power tools and finished with a beautiful polish. The quarries are also the source of naturally grooved, spherical to disk-shaped, and sometimes intergrown concretion
s composed of either hematite
, pyrite
, or wollastonite
, which are collected by gem, mineral, and rock collectors and subject of much folklore.
Town
A town is a human settlement larger than a village but smaller than a city. The size a settlement must be in order to be called a "town" varies considerably in different parts of the world, so that, for example, many American "small towns" seem to British people to be no more than villages, while...
which had a population of 1,274 in 1985. It is situated at an altitude of 1,479 meters (4,855 feet), on the branch railway line from Makwassie in the central North West 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...
. Main routes to and from major population and economic centers, i.e. Pretoria
Pretoria
Pretoria is a city located in the northern part of Gauteng Province, South Africa. It is one of the country's three capital cities, serving as the executive and de facto national capital; the others are Cape Town, the legislative capital, and Bloemfontein, the judicial capital.Pretoria is...
, Johannesburg
Johannesburg
Johannesburg also known as Jozi, Jo'burg or Egoli, is the largest city in South Africa, by population. Johannesburg is the provincial capital of Gauteng, the wealthiest province in South Africa, having the largest economy of any metropolitan region in Sub-Saharan Africa...
and Vereeniging, to Namibia
Namibia
Namibia, officially the Republic of Namibia , is a country in southern Africa whose western border is the Atlantic Ocean. It shares land borders with Angola and Zambia to the north, Botswana to the east and South Africa to the south and east. It gained independence from South Africa on 21 March...
and Botswana
Botswana
Botswana, officially the Republic of Botswana , is a landlocked country located in Southern Africa. The citizens are referred to as "Batswana" . Formerly the British protectorate of Bechuanaland, Botswana adopted its new name after becoming independent within the Commonwealth on 30 September 1966...
pass through it. Ottosdal is a farming community engaged in the growing of grains such as mealies, sunflower
Sunflower
Sunflower is an annual plant native to the Americas. It possesses a large inflorescence . The sunflower got its name from its huge, fiery blooms, whose shape and image is often used to depict the sun. The sunflower has a rough, hairy stem, broad, coarsely toothed, rough leaves and circular heads...
and monkeynuts. In addition, local farmers raise cattle, sheep, pigs, dairy cows and chicken. A major pyrophyllite
Pyrophyllite
Pyrophyllite is a phyllosilicate mineral composed of aluminium silicate hydroxide: Al2Si4O102. It occurs in two more or less distinct varieties, namely, as crystalline folia and as compact masses; distinct crystals are not known....
mine lies near it on the farm Gestoptefontein. This town originated from the establishment of a Dutch Reformed Church
Dutch Reformed Church
The Dutch Reformed Church was a Reformed Christian denomination in the Netherlands. It existed from the 1570s to 2004, the year it merged with the Reformed Churches in the Netherlands and the Evangelical Lutheran Church in the Kingdom of the Netherlands to form the Protestant Church in the...
parish in 1913. To this was added a church building on Korannafontein, the farm of Gerhardus Petrus Otto. Ottosdal grew around the church and was officially registered in 1917 and named after G. P. Otto (de Jager 1997).
Climate
Ottosdal has a relatively hot and dry climate. Summers are very hot. Winter, which seldom last more than two to three months a year, is characterized by cold nights and mild to warm days. The average yearly rainfall is 550 mm (21.6 inches). Precipitation primarily occurs between October to April in the form of heavy thunderstorms during the mid-summer and light rain in the Autumn. Hail can occur between December and February and it only snows once a decade at most. Between August and October, strong winds and dust storms can occur (de Jager 1997).Cultural and historic sites
Some of the cultural and historical sites in and near Ottosdal are:- Trenches, cemeteries and British forts dating to Second Boer WarSecond Boer WarThe Second Boer War was fought from 11 October 1899 until 31 May 1902 between the British Empire and the Afrikaans-speaking Dutch settlers of two independent Boer republics, the South African Republic and the Orange Free State...
, which are located on the farms Gestoptefontein and Driekuil. Driekuil contains structures, which once were the headquarters of Major General Walter Kitchener, a major British Commanders in the western TransvaalSouth African RepublicThe South African Republic , often informally known as the Transvaal Republic, was an independent Boer-ruled country in Southern Africa during the second half of the 19th century. Not to be confused with the present-day Republic of South Africa, it occupied the area later known as the South African...
. Also, there is the "Garden of Remembrance", which contains the graves of soldiers killed during the Second Boer War. - The Ouplaas, one of the few surviving BoerBoerBoer is the Dutch and Afrikaans word for farmer, which came to denote the descendants of the Dutch-speaking settlers of the eastern Cape frontier in Southern Africa during the 18th century, as well as those who left the Cape Colony during the 19th century to settle in the Orange Free State,...
mansions. It was built in 1907 for D. G. van der Merwe by the Italian architect, Sribante. It survives today as the Old Farm Guest House, "Ouplaas Gastehuis", which lies about 13 kilometres (8.1 mi) west of Ottosdal. - The farm Rietkuil which belonged to Boer prophet Siener van RensburgSiener van RensburgNicolaas Pieter Johannes Janse van Rensburg was a Boer from the South African Republic - also known as the Transvaal Republic - and later a citizen of South Africa who was considered by some to be a prophet of the Boere...
. He is buried, along with the members of various other Voortrekker families, near Ottosdal. His prophesies about the Boer War, the 1914-1915 rebellion, the death of General Koos de la Rey and other events brought him to prominence among the Boere and South Africans in general. - Khoisan (Late Stone Age) Rock Engravings on local farms. This rock art included petroglyphs showing game such as elephants, rhinos, ostriches, lions, buffalo, baboons, snakes and giraffes, which once occurred locally in great abundance thousands of years ago.
- A collection of African artifacts housed in a 1910 farmhouse converted to a museum.
- An 1860 water mill, which has been dedicated as a national monument.
- A church belonging to the Dutch Reformed ChurchDutch Reformed ChurchThe Dutch Reformed Church was a Reformed Christian denomination in the Netherlands. It existed from the 1570s to 2004, the year it merged with the Reformed Churches in the Netherlands and the Evangelical Lutheran Church in the Kingdom of the Netherlands to form the Protestant Church in the...
. It was built in 1918; used until 1955; and is now a national heritage site. - and 30 kilometres (18.6 mi) from Ottosdal is the site of the Battle of Boschbult of the Second Boer WarSecond Boer WarThe Second Boer War was fought from 11 October 1899 until 31 May 1902 between the British Empire and the Afrikaans-speaking Dutch settlers of two independent Boer republics, the South African Republic and the Orange Free State...
. It occurred on March 31, 1901.
Pyrophyllite mines
A major industry of the Ottosdal area is the pyrophyllitePyrophyllite
Pyrophyllite is a phyllosilicate mineral composed of aluminium silicate hydroxide: Al2Si4O102. It occurs in two more or less distinct varieties, namely, as crystalline folia and as compact masses; distinct crystals are not known....
mines located on the farm Gestoptefontein. These mines produce a very high quality pyrophyllite, which is a phyllosilicate
Silicate minerals
The silicate minerals make up the largest and most important class of rock-forming minerals, constituting approximately 90 percent of the crust of the Earth. They are classified based on the structure of their silicate group...
mineral
Mineral
A mineral is a naturally occurring solid chemical substance formed through biogeochemical processes, having characteristic chemical composition, highly ordered atomic structure, and specific physical properties. By comparison, a rock is an aggregate of minerals and/or mineraloids and does not...
composed of aluminium
Aluminium
Aluminium or aluminum is a silvery white member of the boron group of chemical elements. It has the symbol Al, and its atomic number is 13. It is not soluble in water under normal circumstances....
silicate
Silicate
A silicate is a compound containing a silicon bearing anion. The great majority of silicates are oxides, but hexafluorosilicate and other anions are also included. This article focuses mainly on the Si-O anions. Silicates comprise the majority of the earth's crust, as well as the other...
hydroxide
Hydroxide
Hydroxide is a diatomic anion with chemical formula OH−. It consists of an oxygen and a hydrogen atom held together by a covalent bond, and carrying a negative electric charge. It is an important but usually minor constituent of water. It functions as a base, as a ligand, a nucleophile, and a...
: AlSi2O5OH. The pyrophyllite is a metamorphosed
Metamorphism
Metamorphism is the solid-state recrystallization of pre-existing rocks due to changes in physical and chemical conditions, primarily heat, pressure, and the introduction of chemically active fluids. Mineralogical, chemical and crystallographic changes can occur during this process...
clay
Clay
Clay is a general term including many combinations of one or more clay minerals with traces of metal oxides and organic matter. Geologic clay deposits are mostly composed of phyllosilicate minerals containing variable amounts of water trapped in the mineral structure.- Formation :Clay minerals...
. The clay was formed by the alteration of volcanic ash
Volcanic ash
Volcanic ash consists of small tephra, which are bits of pulverized rock and glass created by volcanic eruptions, less than in diameter. There are three mechanisms of volcanic ash formation: gas release under decompression causing magmatic eruptions; thermal contraction from chilling on contact...
, which apparently accumulated at the bottom of a quiet body of water. It forms a dense, but soft light grey, or darker, fine-grained stone, which splits into well-defined slabs. The strata
Stratum
In geology and related fields, a stratum is a layer of sedimentary rock or soil with internally consistent characteristics that distinguish it from other layers...
, in which it occurs, is a 3.0 to 3.1 billion year-old, over 2 kilometer-thick assemblage of arenaceous sediments, conglomerates
Conglomerate (geology)
A conglomerate is a rock consisting of individual clasts within a finer-grained matrix that have become cemented together. Conglomerates are sedimentary rocks consisting of rounded fragments and are thus differentiated from breccias, which consist of angular clasts...
, grits, basic volcanics, tuff
Tuff
Tuff is a type of rock consisting of consolidated volcanic ash ejected from vents during a volcanic eruption. Tuff is sometimes called tufa, particularly when used as construction material, although tufa also refers to a quite different rock. Rock that contains greater than 50% tuff is considered...
s, coarse pyroclastic rocks and quartzite
Quartzite
Quartzite is a hard metamorphic rock which was originally sandstone. Sandstone is converted into quartzite through heating and pressure usually related to tectonic compression within orogenic belts. Pure quartzite is usually white to gray, though quartzites often occur in various shades of pink...
called the "Dominion Group".
Originally, pyrophyllite
Pyrophyllite
Pyrophyllite is a phyllosilicate mineral composed of aluminium silicate hydroxide: Al2Si4O102. It occurs in two more or less distinct varieties, namely, as crystalline folia and as compact masses; distinct crystals are not known....
was quarried and locally used for tombstones and building stone and to carve ornaments and utensils such as pots, dishes and cases. Currently, it is milled and processed near where it is mined to produce material used for the production of a wide variety of products. They include acid-resistant lab ceramics, refractory bricks and linings, filler in paint, electrical insulation, boilermaker's chalk, chromic-acid purification pots, and crucibles used in the manufacture polycrystalline-diamonds. Blocks of pyrophyllite are stilled quarried and sold as either "Wonderstone" or "African Stone" for sculpting. It can be easily carved with rasps and power tools and finished with a beautiful polish. The quarries are also the source of naturally grooved, spherical to disk-shaped, and sometimes intergrown concretion
Concretion
A concretion is a volume of sedimentary rock in which a mineral cement fills the porosity . Concretions are often ovoid or spherical in shape, although irregular shapes also occur. The word 'concretion' is derived from the Latin con meaning 'together' and crescere meaning 'to grow'...
s composed of either hematite
Hematite
Hematite, also spelled as haematite, is the mineral form of iron oxide , one of several iron oxides. Hematite crystallizes in the rhombohedral system, and it has the same crystal structure as ilmenite and corundum...
, pyrite
Pyrite
The mineral pyrite, or iron pyrite, is an iron sulfide with the formula FeS2. This mineral's metallic luster and pale-to-normal, brass-yellow hue have earned it the nickname fool's gold because of its resemblance to gold...
, or wollastonite
Wollastonite
Wollastonite is a calcium inosilicate mineral that may contain small amounts of iron, magnesium, and manganese substituting for calcium. It is usually white. It forms when impure limestone or dolostone is subjected to high temperature and pressure sometimes in the presence of silica-bearing fluids...
, which are collected by gem, mineral, and rock collectors and subject of much folklore.
External links
- Lanham, A. 2004. New horizons for Wonderstone, Creamer's Media Mining Weekly Online (December 4, 2004)
- North-West Province