Export of Antiquities:
According to the Antiquities and Art Treasures Act, 1972 (Act No. 52 of 1972), items (including coins) over 100 years old, cannot be exported out of India except with the permission of the Director General, Archaeological Survey of India, Janpath, New Delhi.
Registration of Antiquities:
However, all the antiquities listed as per the following Schedule of the said Amendment, need to be compulsorily be Registered with the Archaeological Survey of India.(http://asi.nic.in/asi_legislations.asp)