There are six sources of raw materials for the production of magnesium: magnesite, dolomite, bischofite, carnallite, serpentine and sea water.These sources differ in the magnesium content, in production methods, and in their origin.Some are mined from mines, some in open mining, others originate in various processes carried out on sea water and salt lakes, and another material originates from the waste of the asbestos production process.agnesium Extraction From Sea Water. The history of elementary magnesium started in 1755,when Joseph Black, a Scottish chemist, discovered that magnesia contained a new element, magnesium.
magnitude definition: Magnitude is defined as large in size or very important. (noun) An example of magnitude is the depth of the Grand Canyon. An example of magnitude is the size of the problem of world hunger. ...
magnitude. 1  greatness, specif. of size. of extent. 2  size or measurable quantity: the magnitude of a velocity. loudness (of sound) importance or influence.