It's perhaps now hard for us to imagine, but not long ago postal administrations were entrusted with very valuable goods.
Perhaps most famously, in 1958 the Hope Diamond was mailed from Harry Winston's New York City jewelry store to the Smithsonian National Museum of Natural History in Washington, D.C. It arrived safely.
Starting in the 1930s the British Post Office carried bank notes and other valuable items between bank offices. The stamps to pay the postage for the heavy mailbags were attached to a separate tag, which the post office canceled appropriately. The tag often had a red label with the white letters "HVP," for high value packet. The package was also often registered, so a registration label was also applied to the tag.
Shown here is a 1969 registered high value packet tag. It was sent from Kyle of Lochalsh, on the northwest coast of Scotland, to Edinburgh. The total postage paid is one pound, fifteen shillings and six pence. The stamps are the £1 and 10/- values from the 1967 printing of the Castles high values (Scott 527-28), the 5/- value from the 1969 Machin high values (Scott MH19) and the 6d value from the 1967 Machin low values (Scott MH9).
The HVP tags gained a bit of infamy when the Great Train Robbery on August 8, 1963, was directed at the Royal Mail train car carrying these packets full of bank notes.
These tags show an interesting use of high value stamps as well as tell the story of an essential postal service.
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