Axinite is a brown to violet-brown, or reddish-brown bladed group of minerals composed of calcium aluminium boro-silicate, (Ca,Fe,Mn)3Al2BO3Si4O12OH. Axinite is pyroelectric and piezoelectric.
The Highveld is the portion of the South African inland plateau which has an altitude above roughly 1500 m, but below 2100 m, thus excluding the Lesotho mountain regions to the south-east of the Highveld. It is home to some of the country's most important commercial farming areas, as well as its largest concentration of metropolitan centres, especially the Gauteng conurbation, which accommodates one-third of South Africa's population.
Tarkwa is a town and is the capital of Tarkwa-Nsuaem Municipal district, a district in the Western Region southwest of South Ghana. Tarkwa has a population of 34,941 people according to 2013 settlement.
Hausmannite is a complex oxide, or a mixed oxide, of manganese containing both di- and tri-valent manganese. Its chemical formula can be represented as MnIIMnIII2O4, or more simply noted as MnO·Mn2O3, or Mn3O4, as commonly done for magnetite, the corresponding iron oxide. It belongs to the spinel group and forms tetragonal crystals. Hausmannite is a brown to black metallic mineral with Mohs hardness of 5.5 and a specific gravity of 4.8.
Sugilite ( SOO-gə-lyte, -jee-) is a relatively rare pink to purple cyclosilicate mineral with the complex chemical formula KNa2(Fe, Mn, Al)2Li3Si12O30. Sugilite crystallizes in the hexagonal system with prismatic crystals. The crystals are rarely found and the form is usually massive. It has a Mohs hardness of 5.5–6.5 and a specific gravity of 2.75–2.80. It is mostly translucent. Sugilite was first described in 1944 by the Japanese petrologist Ken-ichi Sugi (1901–1948) for an occurrence on Iwagi Islet, Japan, where it is found in an aegirine syenite intrusive stock. It is found in a similar environment at Mont Saint-Hilaire, Quebec, Canada. In the Wessels mine in Northern Cape Province of South Africa, sugilite is mined from a strata-bound manganese deposit. It is also reported from Liguria and Tuscany, Italy; New South Wales, Australia and Madhya Pradesh, India.
The second-largest mineral industry in the world is the mineral industry of Africa, which implies large quantities of resources due to Africa being the second largest continent, with 30.37 million square kilometres of land.With a population of 1.4 billion living there, mineral exploration and production constitute significant parts of their economies for many African countries and remain keys to economic growth. Africa is richly endowed with mineral reserves and ranks first in quantity of world reserves for bauxite, cobalt, industrial diamond, phosphate rock, platinum-group metals (PGM), vermiculite, and zirconium.
Manganvesuvianite is a rare mineral with formula Ca19Mn3+(Al,Mn3+,Fe3+)10(Mg,Mn2+)2(Si2O7)4(SiO4)10O(OH)9. The mineral is red to nearly black in color. Discovered in South Africa and described in 2002, it was so named for the prevalence of manganese in its composition and its relation to vesuvianite.
The N'chwaning mine are located in the Northern Cape Province of South Africa. N'chwaning has one of the largest manganese reserves in South Africa having estimated reserves of 323.2 million tonnes of manganese ore grading 42.5% manganese. There are three shafts, designated as N'Chwaning, N'Chwaning II and N'Chwaning III. The majority of the major mineral finds documented originate from the N'Chwaning II shaft.
The Gloria mine is a mine located in the north of South Africa. Gloria represents one of the largest manganese reserve in South Africa having estimated reserves of 156.2 million tonnes of manganese ore grading 33% manganese metal.
The Black Rock mine is a mine located at Hotazel in the Northern Cape province of South Africa. Black Rock represents one of the largest manganese reserves in South Africa having estimated reserves of 70.4 million tonnes of manganese ore grading 39% manganese metal.
The Mamatwan mine is a mine located in the west of South Africa in Northern Cape. Mamatwan represents one of the largest manganese reserves in South Africa having estimated reserves of 433 million tonnes of manganese ore grading 40% manganese metal.
The Middelplaats mine is a mine located in the west of South Africa in Northern Cape. Middelplaats represents one of the largest manganese reserve in South Africa having estimated reserves of 52 million tonnes of manganese ore grading 38% manganese metal.
South32 is a mining and metals company headquartered in Perth, Western Australia. It was spun out of BHP Billiton on 18 May 2015. It is listed on the Australian Securities Exchange with secondary listings on the Johannesburg and London Stock Exchanges.
Cyprine is a copper-rich member of the vesuvianite group with the formula Ca19Cu2+(Al10Mg2)Si18O68(OH)10. A similar name is given to a Cu-bearing variety but not Cu-dominant member within the group. Cyprine (sensu stricto) was discovered in the Wessels mine in the vicinity of Hotazel, Kalahari Manganese Field, South Africa.
Sturmanite is a rare sulfate mineral with the chemical formula Ca6Fe3+2(SO4)2.5(B(OH)4)(OH)12 · 25 H2O. It crystallises in the tetragonal system and it has a Moh's hardness of 2.5. Sturmanite has a bright yellow to amber colour and falls in the ettringite group. It was named after Bozidar Darko Sturman (born 1937), Croatian-Canadian mineralogist and Curator Emeritus of Mineralogy, Royal Ontario Museum.
Scottyite is a barium copper silicate. It was named for Michael Scott, first CEO of Apple. Its type locality is the Wessels mine, Northern Cape, South Africa, where it was first identified. It has also been found at several localities in the Rhineland-Palatinate.
Inesite is a hydrous calcium manganese silicate mineral. Its chemical formula is Ca2Mn7Si10O28(OH)2•5(H2O). Inesite is an inosilicate with a triclinic crystal system. It has a Mohs hardness of 5.5 to 6, and a specific gravity of 3.0. Its name originates from the Greek Ίνες (ines), "fibers" in allusion to its color and habit.
Olmiite is a rare calcium-manganese silicate that was named after an Italian mineralogist called Filippo Olmi. It was approved by the IMA in 2006, being first published in 2007, which makes it a relatively newly discovered mineral. Around 2001, a large amount of specimens believed to be poldervaartite was discovered at the N'Chwaning II mine, which is near the Wessels mine, where the latter was discovered. Only later were the researchers able to determine though their investigations that the two minerals are different, as they are visually indistinguishable. Until Renato Pagano acquired and examined the specimens, seemingly no specific investigation was carried out. Olmiite has been misidentified not only once, but twice. The cream-colored specimens were at first thought to be baryte by the mine geologist.
Effenbergerite is the natural occurrence of the color Han blue.It was first found in the Wessels mine, Kalahari Manganese Field, South Africa. Effenbergerite was approved as a valid mineral species by the IMA in 1993.
