On October 26, 1965, Queen Elizabeth II presented the Beatles their Most Excellent Order of the British Empire (MBE) medals. Four years later, John Lennon returned his, explaining in a letter to the Queen that he was protesting England’s involvement in the Nigerian Civil War and the Vietnam War, as well as the Plastic Ono Band’s song “‘Cold Turkey’ slipping down the charts.” A copy of that letter has now been found in a record sleeve, as CNN points out.

The man who bought the record apparently got it for just £10; the letter it contained is now worth an estimated £60,000 ($72,000). A memorabilia expert has theorized that Lennon sent a different copy to the Queen because he smudged his signature: “If you’re writing to The Queen, you want the letter to look pretty perfect.” See the letter, and listen to “Cold Turkey” (which peaked at No. 14 on the UK Charts), below.

Read “The 200 Best Songs of the 1970s.”