Period 6 element between barium and hafnium, and radium and rutherfordium, respectively. This convention is entirely a matter of aesthetics and formatting practicality; a rarely used wide-formatted periodic table inserts the lanthanide and actinide series in their proper places, as parts of the table's sixth and seventh rows (periods). Lanthanum is a chemical element with the symbol La and atomic number 57. It is the first element in the lanthanide series. It is a soft, ductile, silvery-white metal that tarnishes rapidly when exposed to air and is soft enough to be cut with a knife. It is the eponym of the lanthanide series,
Fire (classical element) temperament (of a person dominated by the yellow bile humour); the masculine; and the eastern point of the compass. In alchemy the chemical element of sulfur was often associated with fire and its alchemical symbol and its symbol was an upward-pointing triangle. In alchemic tradition, metals are incubated by fire in the womb of the Earth and alchemists only accelerate their development. Agni is a Hindu and Vedic deity. The word "agni" is Sanskrit for fire (noun), cognate with Latin "ignis" (the root of English "ignite"), Russian "огонь" (fire), pronounced "agon". Agni has three forms: fire, lightning and the sun.