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A base metal is a common and inexpensive metal, as opposed to a precious metal such as gold or silver. [1] In numismatics , coins often derived their value from the precious metal content; however, base metals have also been used in coins in the past and today.
Earth metal – Old historic term, usually referred to the metals of groups 3 and 13, although sometimes others such as beryllium and chromium are included as well. Heavy metals – Variously-defined group of metals, on the base of their density, atomic number, or toxicity.
A compound semiconductor is a semiconductor compound composed of chemical elements of at least two different species. These semiconductors form for example in periodic table groups 13–15 (old groups III–V), for example of elements from the Boron group (old group III, boron, aluminium, gallium, indium) and from group 15 (old group V, nitrogen, phosphorus, arsenic, antimony, bismuth).
^f Coinage metals: authors differ on whether roentgenium (Rg) is considered a coinage metal. It is in group 11, like the other coinage metals, and is expected to be chemically similar to gold. [ 17 ] On the other hand, being extremely radioactive and short-lived, it cannot actually be used for coinage as the name suggests, and on that basis it ...
This page lists metals, with subdivisions for alloys and specialised subsets of metal and metal-based compounds. Subcategories This category has the following 20 subcategories, out of 20 total.
This is a list of named alloys grouped alphabetically by the metal with the highest percentage. Within these headings, the alloys are also grouped alphabetically. Within these headings, the alloys are also grouped alphabetically.
The platinum-group metals [a] (PGMs) are six noble, precious metallic elements clustered together in the periodic table. These elements are all transition metals in the d-block (groups 8, 9, and 10, periods 5 and 6). [1] The six platinum-group metals are ruthenium, rhodium, palladium, osmium, iridium, and platinum.
Class A metals are metals that form hard acids. [1] Hard acids are acids with relatively ionic bonds. These metals, such as iron, aluminium, titanium, sodium, calcium, and the lanthanides, would rather bond with fluorine than iodine. They form stable products with hard bases, which are bases with ionic bonds. They target molecules such as ...