The earth's core is known to contain tron. Yet geologists do not regard this as a source of the earth's magnetism. Why?

Explanation

(b) Because, temperature at the core of Earth is very high, iron and magnetic ores of iron are in molten state where they do not possess domain structure and hence they are not ferromagnetic. Hence, they are not responsible for terestrial magnetism. (i.e. geo-magnetism).