Question

potash is a non metallic mineral then how can it contain potassium which is a metal

Answer 1

Actually potash is non metallic mineral that contains potassium in water soluble form.
And non metallic here does not mean that potash is a non metal containing mineral.
Actually non metallic minerals are those in which we can not obtain metals by melting process.Wheras in metallic minerals ,metals can be obtained through melting.