The limit of the fusion process is the hydrogen-free allotrope of carbon, graphite.
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Unlike sulfur, however, the red form converts to the gray polymeric allotrope with heat.
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The most stable allotrope of selenium is a dense purplish-gray solid.
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This unstable allotrope, being molecular, is the most volatile, least dense and most toxic.
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A seventh plutonium allotrope exists at very high pressures.
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Even under water, white phosphorus is slowly converted to the more stable red phosphorus allotrope.
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Another coating issue is tin pest, the transformation of tin to a powdery allotrope at low temperature.
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The yellow allotrope of antimony is the most unstable.
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Of the other discovered allotropes, carbon nanofoam is a ferromagnetic allotrope discovered in 1997.
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More examples
A structurally different form of an element; "graphite and diamond are allotropes of carbon"
Any form of an element that has a distinctly different molecular structure to another form of the same element
Element with more than one natural form.
Different bonding arrangements allowing for different forms of matter to be made from a single type of atom. Different forms of matter made in this way are called allotropes. For example, ozone (O3) and dioxygen (O2) are allotropes of the element oxygen. ...
(n) An element which exist in two or more different forms in the same physical state. Diamond and Graphite are both allotropes of carbon yet diamond is hard and graphite is soft. Diamonds crystallize in the cubic crystal system, and Graphite crystallizes in the hexagonal system.
Two or some-more elements with same earthy components though conflicting constructional forms. The earthy and containing alkali properties of assorted allotropic forms of an part of have been all conflicting from any other.