This product is a First Day Cover featuring a commemorative stamp issued in 1987 to celebrate the 300th anniversary of the death of Sir Isaac Newton. The cover is marked with a special cancellation indicating the first day of issue, and the denomination is 18p. This item is a part of British postal history under the reign of Queen Elizabeth II, with a decimal currency system in place. It is a collectible piece for philatelists interested in British stamps and commemoratives from the 1980s.
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