Section 92(1) in The Indian Post Office Rules, 1933
(1)(a)A letter containing currency notes or bank notes and a parcel containing coin, bullion, platinum, precious stones, jewellery or articles of gold or silver, bank notes, currency notes, securities of any kind payable to bearer shall not be accepted for transmission by foreign post unless the sender also agrees to insure it.Provided that in the case of an Insured Letter containing currency notes or bank notes, or an Insured Box containing bullion or gold coin or an Insured Box containing bullion or gold coin or an Insured Parcel containing gold coin, bullion, currency notes or bank notes or any combination of such articles, it shall be insured for the actual value of its contents;
