The principal concentrations of rare earth elements are associated with uncommon varieties of igneous rocks, namely alkaline rocks and carbonatites.
Harmful effects: In healthy people with normal kidney function, a potassium intake from foods does not seem to pose potential for increased risk, because excess potassium is readily excreted in the urine.
In people whose urinary excretion of potassium is impaired, a potassium intake below 4.7 g (120 mmol)/day is appropriate because of adverse cardiac effects.
Rare earth element map: Rare earth element districts in the United States are mainly located in the west.
This map shows the location of potential production locations - enlarge map to see all of the locations.
It is used in the manufacture of soft soaps and as an electrolyte in alkaline batteries.
Potassium chloride is used as a healthier alternative to table salt.
This sequence forms a volcanic chain such as that currently found in the Hawaiian Islands.
Hotspot volcanism forms very large, low gradient shield volcanoes and are similar in composition and eruption style to those found at divergent plate boundaries.
The events seemed to unfold faster than the news media's ability to keep pace.
I remember that day too, for I was driving with a friend in his van in Manhattan.
Like many Americans, I well remember where I was when President Kennedy was assassinated.