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Gold compounds are compounds by the element gold (Au). Although gold is the most noble of the noble metals , [ 1 ] [ 2 ] it still forms many diverse compounds. The oxidation state of gold in its compounds ranges from −1 to +5, but Au(I) and Au(III) dominate its chemistry.
The name is mostly applied informally to compositions between 20–80% gold and 80–20% silver, but these are strictly called gold or silver depending on the dominant element. Analysis of the composition of electrum in ancient Greek coinage dating from about 600 BC shows that the gold content was about 55.5% in the coinage issued by Phocaea .
Gold bullion bars and coins A silver bullion bar. Bullion is non-ferrous metal that has been refined to a high standard of elemental purity. The term is ordinarily applied to bulk metal used in the production of coins and especially to precious metals such as gold and silver.
In 2012, the Perth Mint produced a 1-tonne coin of 99.99% pure gold with a face value of $1 million AUD, making it the largest minted coin in the world with a gold value of around $50 million AUD. [2] China has produced coins in very limited quantities (less than 20 pieces minted) that exceed 8 kilograms (260 ozt) of gold.
In more specialized fields of study and applications the number of elements counted as noble metals can be smaller or larger. It is sometimes used for the three metals copper, silver, and gold which have filled d-bands, while it is often used mainly for silver and gold when discussing surface-enhanced Raman spectroscopy involving metal ...
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Group 11, by modern IUPAC numbering, [1] is a group of chemical elements in the periodic table, consisting of copper (Cu), silver (Ag), gold (Au), and roentgenium (Rg), although no chemical experiments have yet been carried out to confirm that roentgenium behaves like the heavier homologue to gold.
The items we use in everyday life have become such intrinsic parts of our lives, that we've stopped wondering why they are the way that they are a long time ago. From clothes pegs and spaghetti ...