Scute

I have a 6 year old Male Sulcata Tortoise, he is very happy and healthy, last week one of his top scutes popped off. All in one piece like a fingernail popping off. Underneath the scute is new shell growth that is purple and tan in color. There is no fungus or infection but is this normal? I am worried about it and am not sure of he needs to go to the doctors. I do not have a picture but can take one if needed. Please help!