India, King Edward VII, 1907, 2Rs., Block of Six, Overprint Postal Service, used date 30 Dec. 1907, Rare.

The Postal Service overprints on British Indian stamps were first issued in March 1895 for the exclusive use of the Indian post office for the purpose of the accounting of the sum collected as customs duty by the post office on foreign incoming parcels to India.
These stamps were affixed on the receipts of the parcel and cancelled by steel date stamps and or by punching a hole in them. These stamps were withdrawn from the system in 1908.

Gold Stamp Ingot on Cricket from The Empire Collection ...

Gold & Silver Stamp Ingots of The Empire Collection of ...

Extremely Rare POSTAL SERVICE over Print Block of Six o ...

First Aerial Post of 1961.