What is the price of the 21 birthday of Princess Diana's 1982 stamp?

The price of the 21st birthday commemorative stamp of Princess Diana, released in 1982, can vary based on its condition and market demand. Typically, it is valued between a few dollars to over $10 for used examples, while mint condition stamps may fetch higher prices. For the most accurate valuation, it’s best to consult a stamp catalog or a collector's guide.