The legend shows that all of the colorful symbols on the table denote natural occurrences of the ions. In the part shown here, red symbols have to do with ions that go into solid phases at high temperatures. Brown symbols show ions that stay in solids at low temperatures, in weathering, or go into solids at low temperature, and are incorporated into deep-sea ferromanganese nodules. Thus reds and browns will marks ions that reside well in solids.|
Blues and greens, on the other hand, are for symbols having to do with ions that go into solution readily. Blue symbols show the most abundant ions in river water and sea water. Greens show ions that can be limiting or critical nutrients. That relates to solubility, because a nutrient must be sufficiently soluble to be taken from soil water into roots or transported through a cell membrane in an organsim. There's also a blue symbl for ions that enter minerals in igneous rocks relatively late, and thus at lower temperature, and thus also pertains to ions with less affinity for solid phases than those with red symbols.
These symbols are thus placed on the table, depending on natural occurrences reported in the literature. Now we can look at the hard cations again . . . . .
The first slide of this presentation
The last slide of this presentation
Railsback's main page about the Earth Scientist's Periodic Table of the Elements and Their Ions
e-mail to Bruce Railsback (firstname.lastname@example.org)
Railsback's main web page
UGA Geology Department web page