The method of separating a mixture containing chalk powder, iron filings and naphthalene employs the use of a magnet followed by sublimation. At first, a magnet is moved over the mixture. Iron fillings are attracted by the magnet and get separated. Then the chalk powder and naphthalene are separated by sublimation. In this process, the mixture of chalk powder and naphthalene is heated. Naphthalene sublimes on heating, and its vapours are condensed over a cold apparatus. Chalk powder, being nonvolatile, is left behind as residue.