The Two Penny Blue was issued only days after the first plate of the Penny Black in the exact same design. The stamp was rarely used, however, as it was produced exclusively to cover postage for packages weighed over half an ounce.
Like the Penny Black, the Penny Blue’s design was based on the medal engraving created by William Wyon of the monarch when she was only 15-years-old. It was issued in sheets of 240 stamps without perforations. Its design comes in 10 varieties with several different combinations of perforation gauges, watermark sizes, and thickness of white lines on blue paper. In later years, it was also issued in a deeper ink of blue.
Two Penny Blue are ten times rarer, with twice the catalogue value, than its more historic sister, the Penny Black. Owing to the fact that sending such items through the post was a limited occurrence, only small quantities of the stamp were ever produced.
The first edition, from 1840, is by far the most sort after and valuable.
The largest known surviving 38-stamp block of the Plate 1 printing of the 1840 the Two Penny Blue was sold in mint condition to King George V in the 1920s. In 2011, a Post Office Mauritius issue was sold for £1 million in an auction.