Metals

thumb|right|alt=refer to caption|Iron, shown here as fragments and a 1 cm3 cube, is an example of a [[chemical element that is a metal.]] thumb|right|alt=A metal gravy boat|Metal in the form of a gravy boat made from [[stainless steel, an alloy largely composed of iron, chromium and nickel]]

Metallurgy is a domain of materials science and engineering that studies the physical and chemical behavior of metallic elements, their inter-metallic compounds, and their mixtures, which are known as alloys.

The word metalloid comes from the Latin metallum ("metal") and the Greek oeidḗs ("resembling in form or appearance"). However, there is no standard definition of a metalloid and no complete agreement on which elements are metalloids. Despite the lack of specificity, the term remains in use in the literature.

type of chemical bond in metals, sharing conduction electrons among a lattice of cations

loosely defined subset of elements that exhibit metallic properties

common and inexpensive metal

metal of relatively low density

metal that does not contain iron in appreciable amounts

class of metals that are extraordinarily resistant to heat and wear

material consisting of pockets of gas in a metallic matrix

metal that is found in its metallic form, either pure or as an alloy, in nature

toxic and harmful effects of certain metals and their compounds to living organisms

A semimetal is a material with a small energy overlap between the bottom of the conduction band and the top of the valence band, but they do not overlap in momentum space. According to electronic band theory, solids can be classified as insulators, semiconductors, semimetals, or metals. In insulators and semiconductors the filled valence band is separated from an empty conduction band by a band gap. For insulators, the magnitude of the band gap is larger (e.g., >&nbsp;4&nbsp;eV) than that of a semiconductor (e.g., <&nbsp;4&nbsp;eV). Because of the slight overlap between the conduction and vale

thumb|The electronic structure of a half-metal. E_f is the Fermi level, N(E) is the [[density of states for spin down (on the left) and spin up (on the right). In this case, the half-metal is conducting in the minority spin channel.]]

powder made of metal

metal in biology, biochemistry, and medicine

Compare properties if the three main categories in the periodic table

thumb|upright=1.3|Tungsten rods with evaporated crystals, partially oxidized with colorful tarnish Tarnish is a thin layer of corrosion that forms over copper, brass, aluminum, magnesium, neodymium and other similar metals as their outermost layer undergoes a chemical reaction. Tarnish does not always result from the sole effects of oxygen in the air. For example, silver needs hydrogen sulfide to tarnish, although it may tarnish with oxygen over time. It often appears as a dull, gray or black film or coating over metal. Tarnish is a surface phenomenon that is self-limiting, unlike rust. Only t

Metallotolerants are extremophile organisms that are able to survive in environments with a high concentration of dissolved heavy metals. They can be found in environments containing arsenic, cadmium, copper, and zinc. Known metallotolerants include Ferroplasma sp. and Cupriavidus metallidurans.

relevance of metallic elements in biomedical contexts

metals discovered by humans in prehistoric times