Michael Whitfield, age 12 of Victoria, for his question:
Where does aluminum come from?
Two minerals were used to make your aluminum frying pan;, One may have been toted all the way from South America: The other may have been hauled from Greenland in the north. This is strange, for aluminum is the most common metal in the earth, There are traces of it in clay and in most rock But we need richer concentrates, ores, before it is profitable to extract it.
The favorite ore is bauxite. There is some bauxite in North America, but not enough to make all the aluminum we need. More is imported from South America and the West Indies. The ore is crushed and refined to become aluminum oxide.
Next the oxygen is driven off from this substance. It is done by electrolysis. In a bath of carbon, aluminum oxide is mixed with cryolite, or ice stone. An electric current passes through the bath. Carbon dioxide bubbles up and pure aluminum settles to the bottom. The mineral cryolite may be made synthetically. There are natural deposites of it in Greenland, from where some of it is still imported.