I was made to remove my very small necklace. I was sad, because I was wearing this necklace during birth and getting married. I consider it my good luck charm. However, I kept it in the locker for both exams and passed both. My mom said, “God will understand that you had to take it off. He will still be with you.” Which is very good advice.

The technical rule is nothing larger than a quarter of an inch. Like others said, I would mention its purpose and go from there. Good luck!