Historically, nickel sulfides have been the primary source for nickel, but in recent decades there has been a resurgence in lateritic ore mining. In serpentinite, pockets and fissures can contain minor amounts of garnierite with high quantities of nickel content (20-40%). They are largely Mg-depleted serpentine containing 1.5-2.5% nickel. Saprolite type nickel ores are found below the limonite zone. Because of erosion it is possible that the limonite zone is missing. It consists of goethite, which itself incorporates 1-2% nickel. Limonite is highly enriched in iron due to strong leaching of magnesium and silica. There are two types of lateritic nickel ores: limonite and silicate types. Some examples are dunite, komatiite and peridotite along with their serpentinized derivatives, and serpentinite. Lateritic nickel ores are formed from weathering of ultramafic rocks rich in olivine. Itis found in geological complexes throughout this world which may be the basis for its exclusive use. The composition of Pentlandite consists of approximately 34% nickel. Pentlandite is the most common nickel sulfide and is typically formed during the cooling of sulfide melts caused by host rock contact with magmatic or metamorphic processes, or from meteoric impact. Apart from its direct use elemental nickel (along with silver, copper, lead, and others) is one of many pathfinder minerals that are geochemical indicators for gold. Lateritic ores are located on the earth's surface in tropical regions while sulfides are found worldwide underground. Nickel is found in either nickel-copper sulfides or in laterites. Up until recently sulfide ores were mainly used to extract nickel. Nickel became popular for plating and alloys such as 'nickel silver' (German silver) in the 19th century. The name nickel comes from the Saxon word kupfernickel 'devil's copper' due to miners inability to extract copper from it. Nickel was first isolated and classified in 1751 as a chemical element by Axel Fredrik Cronstedt after he initially mistook the ore for a copper containing mineral. In Chinese documents dated around 1500 BC, there is reference to a 'white copper', which is believed to be something similar to a nickel-silver alloy. For example, in ancient Egypt artifacts, made of nickel containing meteoric metal, were discovered in graves dating back to about 3500 BC. Nickel like materials have been unintentional used throughout the ancient world. Some current major nickel producing nations are Indonesia, the Philippines, and New Caledonia. Over 65% of global nickel production is used for stainless steel with the rest being used for a nickel and copper-based alloy, alloy steel, and batteries to name a few. In modern times nickel has been primarily used for alloy creation. It was isolated and classified in 1751, being mistaken as a copper mineral, and later was used for plating and alloys. Nickel is one of four elements that are ferromagnetic at average room temperature and pressure. This because the earth is believed to have an iron-nickel core. Even though it is the fifth most abundant element on earth there is only about 0.01% in the earth's crust. Even with these characteristics, all nickel alloy are ductile and malleable. It is a silvery-white, shiny metal that is strong and resistant to corrosion, making nickel beneficial to add to strengthen metal alloys. Nickel is an element on the periodic table with an atomic number of 28 and chemical symbol Ni. Nickel prices have tended to range between $5 and $10 USD per pound. Most nickel is used in the production of stainless steel.
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