Calcium, chemical element. Properties and characteristics

Calcium, chemical element. Properties and characteristics

Calcium is a chemical element with the symbol Ca and atomic number 20.

It is the fifth most abundant mineral in the earth's crust and is essential for life on Earth. Reacts with water to form calcium hydroxide.

What kind of metal is calcium?

Calcium is a silvery-white alkaline earth metal. It is a lipophilic element, found mainly in the crust on Earth, consisting of approximately 4.15 percent by weight of this element. 

Due to its reactive properties, it does not occur in the free state. Known minerals that contain this element are calcite, gypsum (calcium sulfate) and fluorite (calcium fluoride). It can generally be obtained by isolating it by electrolysis from other compounds.

What is calcium for?

Calcium compounds form the basis of bones and teeth, so it is important that many organisms get enough of them. Getting an excess of the mineral can lead to Wobbler in young animals or kidney stone problems.

Importance in the industry

The uses of this element in the industry are:

  • Reducing agent in the extraction of other metals such as uranium, zirconium and thorium.

  • In the form of calcium oxide, it is the raw material for many building materials such as cement.

  • Deoxidizer for all types of alloys

Furthermore, this mineral is also used as a metal in alloys, especially in combination with aluminum, beryllium, copper, lead and magnesium.

Function in the human body

Calcium is the most abundant mineral found in the human body. Teeth and bones contain the most.

In the body, it has a role in:

  • Bone mineralization (bone formation)

  • Blood clotting

  • The potential of the plasma membrane

  • Muscle contraction

  • The release of hormones

  • Glycogen metabolism

  • Cell division.

It is found in the skeleton (99%), in tissues, and in extracellular fluids (including blood).

These are the recommended amounts per day for age groups of an adequate calcium diet.

Age range

Recommended amount

0 - 6 months

200 mg

7 - 12 months

260 mg

13 years

700 mg

48 years

1,000 mg

9 - 13 years

1,300 mg

14 to 18 years

1,300 mg

19 to 50 years

1,000 mg

Men ages 51 to 70

1,000 mg

Women 51 to 70

1,200 mg

71 years or older

1,200 mg

Pregnant or breastfeeding teens

1,300 mg

Pregnant or breastfeeding adult women

1,000 mg


What foods have a lot of calcium?

A varied diet ensures sufficient absorption of calcium by the body. For diets rich in calcium, the main sources of calcium are:

  • Milk and dairy products. 100 ml of whole, semi-skimmed and skimmed milk contains 110 mg of calcium.

  • Vegetables like Chinese cabbage or kale

  • Nuts

  • Vegetables.

It is possible to take calcium supplements when calcium intake in the diet is insufficient, for example in people with lactose intolerance. There are supplements in the form of calcium citrate or calcium carbonate, in the form of effervescent and chewable tablets.

How is it regulated in the body?

The level of calcium in mammals is regulated, in part thanks to the bones that act as a storage site. The ions of this mineral are released from there into the bloodstream under controlled conditions. In the bloodstream, it is transported as dissolved ions or bound to proteins such as albumin.

In the clinical chemistry laboratory, it is measured primarily in the blood; its level may indicate an imbalance of this mineral in body compartments.

The level in the blood is regulated by vitamin D and the hormone PTH.

Publication Date: August 26, 2021
Last Revision: August 26, 2021