Ca

Calcium

Calcium is the fifth most abundant element in the earth’s crust and the most abundant mineral in the human body. It is a silvery-white, soft metal with atomic number 20.

Calcium is essential for maintaining strong bones and teeth, and regulating muscle contractions, nerve signaling, blood clotting and hormone secretion. About 99% is stored in bones and teeth, while the remaining 1% circulates in blood and tissues. Calcium is found naturally in foods like dairy products, leafy green vegetables, and fish with edible bones. 

Calcium compounds are used in construction materials, paper production, and as reducing agents in metallurgy. The element’s reactivity means it is rarely found in its pure form in nature, instead occurring in compounds like limestone (calcium carbonate), gypsum (calcium sulfate), and fluorite (calcium fluoride).