Identifying Sodium Minerals

Flame Test. Sodium compounds when heated give a strong and persistent yellow flame. The test is very delicate and must be used with care, for only a trace of sodium may yield a distinct flame. It the mineral contains sodium in any notable amount, it should give an intense and continuous flame color.

Alkaline Reaction. A compound of sodium with a volatile acid yields after ignition a residue that reacts alkaline on a moistened test paper.