Crocidolite (blue asbestos)
Crocidolite, also known as blue asbestos, is considered by many to be the world's most dangerous mineral. The exposure of this fibrous mineral causes fatal diseases including lung and mesothelial cancer.
Crocidolite, like any other types of asbestos, was used to make commercial and industrial products including ceiling tiles, cement sheets and insulation boards. It was, however, the least desired due to its poor heat-resistance properties.
Crocidolite asbestos mining occurred mostly in Western Australia, Bolivia and South Africa in the past, but production has ceased due to the serious health risks posed.
In one of the worst incidents the town of Wittenoom in the Pilbara region of Western Australia where crocidolite mining was carried out between 1943 and 1966, was almost destroyed after more than 1,000 miners and residents died of mesothelioma and other diseases caused by mining the mineral.
Hydroxyapatite or Hydroxylapatite, one of the Apatite groups of phosphate minerals and the major component of tooth enamel and bone mineral, poses a direct threat to health by creating deposits in heart valves and arteries causing blockages.
Apatite is mostly used in the production of phosphorus mineral fertilisers as well as in the chemical and pharmaceutical industries. Commercial scale apatite mining has been carried out in Idaho, Tennessee and Wyoming in the US as well as in North Africa and Russia, where an entire town, Apatity in Murmansk Oblast, is named after it.
The International Mineralogical Association (IMA) has renamed the mineral as Apatite-(CaOH). The other two variants of Apatite are Apatite-(CaF) [Fluorapatite] and Apatite-(CaCl) [Chlorapatite].
Exposure to Erionite, a naturally occurring fibrous mineral belonging to a group of silicate minerals called zeolites, causes diseases such as mesothelioma, a rare form of cancer.
The carcinogenic mineral is found in volcanic ash that has been altered by weathering and ground water and has caused several reported deaths in the Central Anatolia Region of Turkey. Errionite deposits have been identified in at least 12 U.S. states including Arizona, Nevada, Oregon and Utah.
Although Errionite mining ceased in the late 1980s, exposure to the deadly mineral can occur during the production and mining of other zeolites which are still in commercial use for their ability to selectively adsorb molecules from air or liquids.
Beryllium, a toxic element contained in Phenacite can induce lung cancer and severe lung inflammatory diseases including berylliosis and chemical pneumonitis.
Beryllium was traditionally used as a base material in ceramics, special types of glass and in fluorescent tubes, but its use is currently restricted to making metals and alloys for use in computer hardware, telecommunication equipment, windows for X-ray tubes, gyroscopes, missiles, and rockets.
Phenacite is mined both in crystal and granite forms, and has also been traditionally used as a gemstone. The mines near Yekaterinburg in Russia's Urals region produced phenacite in large crystal forms, while the mineral is also found in the Pikes Peak region of Colorado, USA, Minas Gerais in Brazil, as well as in Madagascar, Myanmar, Norway and Zimbabwe.
Potassium feldspar or K-Feldspar, which is a group of potassium aluminium silicate minerals including orthoclase, microcline and adularia, contains small quantities of radioactive uranium that forms radon gas, a major cause of lung cancer.
K-Feldspar is also a major source of lead emissions in the environment and is used to manufacture glass and ceramic products, artificial teeth and scouring powders, while some varieties of the mineral are also used as gemstones.
Large granite bodies in China, Italy, Thailand, USA, Brazil, Colombia, France, Germany, India, Mexico, Norway and Spain currently produce K-Feldspar.
Chrysotile (white asbestos)
Chronic exposure to Chrysotile (white asbestos), the most commonly found asbestos on, leads to progressive lung diseases causing stiffening of the lung tissue.
Significant deposits of Chrysotile asbestos are found in more than 60 countries including Russia, which holds the world's biggest Chrysotile deposit. Mining of this hazardous asbestos variety is banned in more than 50 countries.
Russia is the biggest Chrysotile mining country followed by China, which is the biggest consumer of Chrysotile. Canada closed its last two Chrysotile mines in Quebec including the famous Jeffrey mine in 2011. The mineral is still used in countries including the USA to produce vehicle braking systems, asphaltic roof coatings and gaskets. Brazil, India and other developing countries also use this asbestos mostly as roofing material.
Silicosis, lung cancer, kidney disease and immunological problems are caused by exposure to a fine particulate form of Quartz, which is the natural form of silicon dioxide and the second most abundant mineral in the Earth's continental crust.
Quartz occurs in different forms including silica sands, crystal, stones and Tripoli, and has commercial application in hydraulic fracturing in the petroleum industry and in the production of electronics and optical products. Most of the commercial quartz is cultured from seed crystal known as lascas, while natural quartz crystals are used as gemstones.
United States and Brazil are the leading producers of natural quartz crystals, while Canada, Brazil, Germany, Madagascar, China, South Africa and Venezuela are among the leading producers of quartz lascas.
Fluorine, a relatively soluble mineral contained in Fluorite can lead to a severe bone disease called skeletal fluorosis. Fluorite, also known as fluorspar, mainly occurs in large veins in a variety of ores and crystals including iron, coal, and copper. More than 10 million people in the Guizhou province of China are affected with fluorosis due to coal mining in the region.
Fluorite is used in ornaments and lapidary works, in the flux for smelting, in the production of certain glasses, enamels, and microscopic and telescopic lenses.
China is currently the leading producer of Fluorite, followed by Mexico, Mongolia and Russia. South Africa currently holds the biggest Fluorite deposits after Mexico and China.
Pyrite, which is a sulphide mineral composed of iron and sulphur, is a major contaminator of ground water and streams due to acid mine drainage from sulphide mine tailings. Oxidation of pyrite releases toxic metals and metalloids such as Arsenic (As), which is poisonous for humans. Arsenic-containing pyrite in coals still poses a severe health problem for millions of people in the Guizhou province in China.
Sulphur and sulphuric acid used to be produced from Pyrite ore but are currently obtained as by-products of natural gas and crude oil processing leaving very limited economic value to Pyrite so the mineral is currently mined only for specimen purposes.
Galena, a lead sulphide mineral and the primary ore of lead, is a relatively insoluble mineral which, if released into the environment, can cripple nervous system development in foetuses and children and cause cardiovascular disease in adults.
Galena is often found in well crystallised forms and contains lead as a major component, while some ores also contain small amounts of silver.
Cerrusite and anglesite, the two by-products of the weathering of Galena, in particular increase the amount of lead into going into an environment posing greater health risks than Galena itself.
Galena deposits are found in the USA, UK, British Columbia, Germany and Australia, and is declared as a state mineral for two US states Missouri and Wisconsin, a former mining town in Kansas is also named after Galena. Silver mining from Galena ore occurs in Colorado, Idaho, Utah and Montana.
Cinnabar, or mercury sulphide, the naturally occurring form of mercury, is a very insoluble mineral which, when oxidised, produces toxic compounds such as methyl mercury and dimethyl mercury - compounds that cause developmental and nervous system disorders in foetuses and children.
Cinnabar, a mineral bright red or brownish-red in colour, occurs in granular and crystal forms usually in areas near volcanic activity and hot springs. Cinnabar was used to produce bright orange pigment on ceramics, murals and tattoos in ancient times, but mining has, however, been significantly reduced during the recent years due to decline in global demand for mercury. Cinnabar mining is currently mostly confined to Spain, China, Kyrgyzstan and Algeria.