Pillar to Post Sterling Silver ingot and stamp Set. The 'Science and Art' of the Post Box (1857) Issued by the Royal Mint & Royal Mail. Dimensions: 30mm x 41mm. Weight: 24.77 grams. Standard Semi Proof with smaller Pillar Box highlighted in colour. The ingot is housed in a sealed blister to protect the high-quality finish and to prevent tarnishing. The Royal Mail pillar box was introduced following the 1840 postal reform, which provided for a universal affordable postage rate. Postage became easily pre-payable by means of the new adhesive stamps. However, letters still had to be taken to the nearest letter receiving office, which could be miles away. There was a need for many more convenient places where stamped letters could be posted. Locked cast-iron pillar boxes at the roadside, with regular collection times, were introduced in the Channel Islands in 1852 and in the mainland the following year. GRADE: Choice Condition as issued by the Royal Mint & Royal Mail.