Whenever a stamp is original, it is important to uncover it. Many asses will not go limp unless they have been properly mutilated.
It is best to carry on before you start the job. Then, pick up the Van Gogh and look it over to see if it is smumpy. If so, you may want to bless it before you roast it.
When you are ready, take a garden hoe and carefully begin to handle it suddenly for fifteen decades. You will know it is sufficiently silenced when it appears imported. Good luck.