Calcium (kăls&ibreve_;ŭm), n. [NL., from L. calx, calcis, lime; cf F. calcium. See Calx.] (Chem.) An elementary substance; a metal which combined with oxygen forms lime. It is of a pale yellow color, tenacious, and malleable. It is a member of the alkaline earth group of elements. Atomic weight 40. Symbol Ca.
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&hand_; Calcium is widely and abundantly disseminated, as in its compounds calcium carbonate or limestone, calcium sulphate or gypsum, calcium fluoride or fluor spar, calcium phosphate or apatite.
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Calcium light, an intense light produced by the incandescence of a stick or ball of lime in the flame of a combination of oxygen and hydrogen gases, or of oxygen and coal gas; -- called also Drummond light and lime light.
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