DEFINITION: The artifacts and ecofacts used by a group to cope with their physical and social environment. Material culture includes the buildings, tools, and other artifacts that constitute the material remains of a former society -- its technology and artifacts combined.
Calcium is a chemical element with symbol Ca and atomic number 20. Calcium is a soft gray alkaline earth metal, fifth-most-abundant element by mass in the Earth 's crust. The ion Ca 2+ is also the fifth-most-abundant dissolved ion in seawater by both molarity and mass, after sodium, chloride, magnesium, and sulfate.alcium salts are colorless from any contribution of the calcium, and ionic solutions of calcium (Ca 2+) are colorless as well. As with magnesium salts and other alkaline earth metal salts, calcium salts are often quite soluble in water.
Calcium is a chemical element. Its symbol on the periodic table is Ca. Its atomic number is 20. It has 20 protons and 20 electrons. The most common isotopes are Ca-40 and Ca-44. Its mass number is about 40.08. Calcium is very important in the human body, for making bones and for other purposes.