|Systematic name||Calcium carbonate|
|Other names|| Limestone|
|Molar mass||Molar mass::100.087 g/mol|
|CAS number||CAS number::471-34-1|
|Density and phase||[[Density::2.83 g/cm3]], solid.|
|Solubility in water||Insoluble|
|Melting point||Melting point::825°C|
|MSDS||External MSDS Data|
|Main hazards||Not hazardous|
|R/S statement|| R: R36, R37, R38 |
S: S26, S36
Calcium carbonate is an organic compound composed of carbon, oxygen, and calcium. It is a white powder that was traditionally used as a blackboard chalk. Other names for calcium carbonate are: limestone, calcite, aragonite, chalk, and marble. It can be found all over the world and is incredibly useful. Calcium Carbonate is found naturally but can also be man made. Not only have humans used calcium for the past couple hundred years, but also thousands of years ago.
Carbon, oxygen, and calcium are the three elements that calcium carbonate is composed of. It is a white solid that is nontoxic and odorless. Calcium carbonate is found all over the world as rock. It is also dissolved in rivers and oceans. The Earth's crust contains more than four percent calcium carbonate, therefore making it one of nature's most abundant raw materials . The most common forms found are marble, limestone, and chalk. These three forms may be identical in chemical terms, but they differ greatly in purity, whiteness, thickness, and homogeneity .
Calcite comes from its chemical component calcium carbonate. Calcite is known in over three hundred crystal forms. Scalenohedral crystals of calcite are usually known as dogtooth spar or dogtooth calcite. .
Places of natural occurrences of Calcium carbonate are bivalve shells, bryozoans, calcisol, carbonate rock, cave deposites, corals, ground water, horn corals, invertebrate integumentary systems, mettle and mulberry families, playas, seawater, snail shells, and water falls  Commercial carbonate can be produced two ways, "through the extraction and processing of ores or synthetically through chemical precipitation", this is called Ground Calcium Carbonate (GCC). Precipitated Calcium Carbonate (PCC) is made "through a recarbonisation process or as a by-product of some bulk chemical processes" 
Other forms or synonyms of calcium carbonate powder are: precipitated calcium carbonate, limestone, ground/pulverized calcium carbonate, calcite, GCC, PCC, crushed marble, lime chalk, whiting, French Chalk, champagne chalk, albacar, aeromatt, and calcium carbonate nanoparticle .
Calcium is needed in the body for a healthy heart, bones, and nervous system. Calcium carbonate is a supplement that is taken when not enough calcium is being taken in through the diet and comes in the form of a tablet. The medication sometimes has other uses such as relieving heartburn, acid indigestion, and upset stomach, so ask your doctor for more information.
Brand names of calcium carbonate are: Alka-mints, Alkets, Alkums, Amilac, Amitone, Cal Gest, CalCarb, Calci-Chew, Calci-Mix, Calcitab, Caltrate, Caltro, Chooz, Dicarbosil, Equilet, Extra Strength Mylanta Calci Tabs, Maalox Antacid Barrier, Maalox Children's, Maalox Quick Dissolve, Maalox Quick Dissolve Maximum Strength, Mylanta Child, Nepro Calci, OsCal 500, Oysco 500, Oyst Cal, Oyst Cal 500, Pepto-Bismol Children's, Rolaids Sodium Free, Rolaids Softcheps, Titralac, Tums, Ultra Mylanta Calci Tabs, Uni-Cal 500, and Uni-Mint. Some side effects that calcium carbonate have are: upset stomach, loss of appetite, vomiting, stomach pain, belching, constipation, dry mouth, metallic taste, and increased urination 
Uses other than medical reasons for calcium carbonate are: building materials in construction, paper, plastics, paints, and coatings. Calcium carbonate is very important to the construction industry. Calcium carbonate decomposes to form lime and carbon dioxide. These two products are important in the making of steel, paper, and glass. It also helps in the making of mortar that is used in the bonding of bricks, stones, concrete blocks, roofing shingles, tiles, rubber compounds ,plastic filler, ceramic flux, asphalt filler, chemical processing, glass ingredient, water treatment, pesticide granules, dusting agent, welding rods roating, theroplastics, thermosets, paints, coatings, adhesives, and sealants . The most widely used mineral in the making of paper, paints, coatings, and plastics is none other than calcium carbonate . Just some other examples of some uses for calcium carbonate are: plastics, rubber, coatings, inks, adhesives, and soil conditioner . All these uses makes it one of the most useful and versatile materials known to man .
Calcium carbonate has been used for thousands of years, even before Christ was born. It has been found in prehistoric cave paintings. The Anglo-Saxons called chalk Hwiting-melu meaning whitening powder .
Calcium carbonate otherwise known as limestone, used to be called calx by the Romans. The Romans would heat the the calx, getting rid of carbon dioxide to be left with calcium oxide. When this is mixed with water, it forms cement. With this access to cement, the Romans built massive amphitheaters and aquaducts 
Calcite is from a Greek word that means lime. 
- Author Unknown. Calcium Carbonate - an exceptional mineral. British Calcium Carbonates Federation. Web. Date Accessed 30 January 2012.
- Author Unknown. Calcium Carbonate. Industrial Minerals Association North America. Web. Accessed 30 January 2012 .
- Author Unknown. Calcite. Ohio History Central. Web. 1 July 2005.
- Author Unknown. Calcium Carbonate. Encyclopedia Britannica. Web. Accessed 30 January 2012.
- Author Unknown. Calcium Carbonate Powder. Reade. Web. 4 February 2006.
- Author Unknown. Calcium Carbonate. PubMed Health. Web. 1 September 2010.
- Author Unknown. Calcium Element Facts. Chemicool. Web. 14 May 2011.