The Rule is here:-
3.8 Lost, misplaced, torn or mutilated tickets: - If the reservation status of a lost, misplaced, torn or mutilated ticket, at the time of receipt of the application for issuance of a duplicate ticket for the purpose of undertaking journey, is confirmed or RAC and that the duplicate ticket is sought before preparation of reservation chart of the concerned train, the station master shall issue a duplicate ticket in lieu of the original ticket on payment of rupees fifty per passenger in case of second and sleeper class and rupees one hundred per passenger for other classes instead of existing clerkage charge