If her ring is on her finger, then she knows where it is at all times. For all we know, she could have had a duplicate made to wear 24/7 and the "real" ring is sequestered in a vault somewhere with armed guards on duty and will never see the light of day again and be totally forgotten.
We now return you to the discussion of daytime fashion.
It's her special "active duty" duplicate and underneath the "stone" is a hidden compartment for lip moisturizer and a piece of gum.