Graphology - the study of handwritings; autograph - written with one's own hand; seismograph - a machine noting strength and duration of earthquakes. marina - a harbor for pleasure boats; maritime - relating to the sea; submarine - an undersea boat; aquamarine - color of sea water.
Chemicals are classified into various hazard classifications in accordance with their physiochemical properties and health hazards. Each class of chemical has a pictorial symbol called a danger symbol.
Mineral Groups. One of the first steps in studying a group, such as minerals, is to subdivide them according to similarities they may have with one another. This is called classification. Minerals are classified according to chemical composition. There are seven major chemical groups. There are also several minor groups. These include: the sulfosalts, nitrates, borates, tungstates and molybdates, and the phosphates, arsenates, and vanadates.