The Molten mixture contaning Cu₂S and FeS is called

If the density of the gangue is less what method is used ?

Which is used for making utensils ,many scientific instruments, telescope,microscopes etc.?

Metals except sodium and potassium have

A mineral from which a metal can be extracted on a commercial scale economically and easily, is called

Ores usually contain unwanted earthly materials called

Non-metals are

Which non-metal is the hardest natural substance known?

Non-metals react with halogens to give