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This is a list of prices of chemical elements. Listed here are mainly average market prices for bulk trade of commodities. Data on elements' abundance in Earth's crust is added for comparison. As of 2020, the most expensive non-synthetic element by both mass and volume is rhodium.
Binary metal-boron compounds, the metal borides, contain only boron and a metal. They are metallic, very hard, with high melting points. TiB 2, ZrB 2, and HfB 2 have melting points above 3000 °C. [68] Some metal borides find specialized applications as hard materials for cutting tools. [71]
Ferroboron (CAS Registry Number 11108–67-1) is a ferroalloy of iron and boron with boron content between 17.5 and 20%.[1]It is manufactured either by carbothermic reduction of boric acid in an electric arc furnace together with carbon steel, or by the aluminothermic reduction of boric acid in the presence of iron.
Soluble boron arranges in steels along grain boundaries. This inhibits the γ-α transformations (austenite to ferrite transformation) by diffusion and therefore increases the hardenability, with an optimal range of ~ 0.0003 to 0.003% B. [1] Additionally Fe 2 B has been found to precipitate at grain boundaries, which may also retard the γ-α transformations . [1]
Aluminium, in contrast to boron, is the most abundant metal in the Earth's crust, and the third most abundant element. It composes about 8.2% (82,000 ppm) of the Earth's crust, surpassed only by oxygen and silicon. [41] It is like boron, however, in that it is uncommon in nature as a free element.
Recent excavations in Middle Ganga Valley done by archaeologist Rakesh Tewari show iron working in India may have begun as early as 1800 BCE. [5] Archaeological sites in India, such as Malhar, Dadupur, Raja Nala Ka Tila and Lahuradewa in the state of Uttar Pradesh show iron implements in the period between 1800 BCE – 1200 BCE.
Metal prices are the prices of metal as a commodity that are traded in bulk at a predefined purity or grade. Metal can be split into three major categories, precious metals, industrial metals and other metals. Precious metals and industrial metals are priced by trading of those metals on commodities exchanges. [1]
Arnold, David (2004), The New Cambridge History of India: Science, Technology and Medicine in Colonial India, Cambridge University Press, ISBN 0-521-56319-4. Balasubramaniam, R. (2002), Delhi Iron Pillar: New Insights, Indian Institute of Advanced Studies, ISBN 81-7305-223-9. Bouri, Nisha.