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The name calcium is derived from the word “calx” that is Latin for lime. The history of calcium dates to 7000 BC, when calcium in the form of lime was used as plasters for making statues and as building material. Calcium is important nutrient for the human body.

It was discovered in 1787 by Antoine Lavoisier and was isolated in pure form in 1808. All rights reserved.Calcium is an alkaline earth metal and has been known since prehistoric times. Copyright © 2022, Columbia University Press. The Columbia Electronic Encyclopedia, 6th ed. Calcium also functions in the regulation of the heartbeat and in the conversion of prothrombin to thrombin, a necessary step in the clotting of blood.

A sufficient store of vitamin D (see under vitamin) in the body is necessary for the proper utilization of calcium. In the human adult the bone calcium is chiefly in the form of the phosphate and carbonate salts. It is a constituent of most plant and animal matter.Ĭalcium is essential to the formation and maintenance of strong bones and teeth the recommended daily dietary allowance for all but young children ranges from 1,000 to 1,300 milligrams. It is found widely distributed in its compounds, e.g., Iceland spar, marble, limestone, feldspar, apatite, calcite, dolomite, fluorite, garnet, and labradorite. Generally, calcium compounds show an orange or yellow-red color when held in the Bunsen burner flame.Īlthough calcium is the fifth most abundant element in the earth's crust, of which it constitutes about 3.6%, it is not found uncombined. Calcium bicarbonate causes temporary hardness in water calcium sulfate causes permanent hardness. The arsenate and the cyanide are used as insecticides. The phosphate is a major constituent of bone ash. Calcium carbide reacts with water to form acetylene gas it is also used to prepare calcium cyanamide, which is used as a fertilizer. Tremolite, a form of asbestos, is a naturally occurring compound of calcium, magnesium, silicon, and oxygen. The element is a constituent of lime (see calcium oxide), chloride of lime (bleaching powder), mortar, plaster, cement (see cement, concrete, whiting, putty, precipitated chalk, gypsum, and plaster of Paris. The metal is of little commercial importance compared to its compounds, which are widely and diversely used. It is used in alloys with other metals, such as aluminum, lead, or copper in preparation of other metals, such as thorium and uranium, by reduction and (like barium) in the manufacture of vacuum tubes to remove residual gases. Today, calcium metal is usually prepared by electrolysis of fused calcium chloride to which a little calcium fluoride has been added. It combines with other elements, e.g., with oxygen, carbon, hydrogen, chlorine, fluorine, arsenic, phosphorus, and sulfur, forming many compounds.Īlthough lime (calcium oxide) has been known since ancient times, elemental calcium was first isolated by Sir Humphry Davy in 1808.

It reacts directly with water, forming the hydroxide. Calcium is chemically active it tarnishes rapidly when exposed to air and burns with a bright yellow-red flame when heated, mainly forming the nitride. Chemically it resembles strontium and barium it is classed with them as an alkaline-earth metal in Group 2 of the periodic table. Calcium is a malleable, ductile, silver-white, relatively soft metal with face-centered, cubic crystalline structure. Calcium kăl´sēəm, metallic chemical element symbol Ca at.