Muslims insist that the Qur'an they have today goes all the way back to Muhammad and has never been changed or altered. However, in 1972 during a renovation of the great mosque in Sana'a, Yemen, this palimpsest was discovered. But it turns out that we have two different manuscripts with edits written on this one palimpsest. Amazing.
Learn more by listening to this talk by Al Fadi, a convert from Saudi Arabia. He is also founder and president of CIRA International.