What is the value of Princess Diana 21st birthday Falklands stamp?

The value of the Princess Diana 21st birthday Falklands stamp can vary depending on its condition and market demand. Generally, these stamps are not considered highly valuable among collectors, often ranging from a few dollars to around $20. However, unique items or those in pristine condition may fetch higher prices. It's best to consult a stamp collector or a reputable auction house for a more accurate appraisal.