Symbol (chemistry) the material was known in ancient times, while for others, the name is a more recent invention. For example, "He" is the symbol for helium (New Latin name, not known in ancient Roman times), "Pb" for lead ("plumbum" in Latin), and "Hg" for mercury ("hydrargyrum" in Greek). Some symbols come from other sources, like "W" for tungsten ("Wolfram" in German, not known in Roman times). Temporary symbols assigned to newly or not-yet synthesized elements use 3-letter symbols based on their atomic numbers. For example, "Uno" was the temporary symbol for hassium (element 108) which had the temporary name of "unniloctium".
Flux melting the mantle, where these volatiles are released by metamorphic dewatering into the overlying mantle wedge. The partial melting triggered by the incorporation of volatiles produces mafic magma which rises and differentiates forming the igneous and volcanic rocks of the overlying volcanic arc. Flux melting In igneous petrology, flux melting occurs when water and other volatile components are added to hot solid rock. In engineering and metallurgy, flux is a substance, such as salt, that produces a low melting point mixture with a metal oxide. In the same way, the addition of water and other volatile compounds to rocks composed of