"Well, firstly, you told me yourself that You-Know-Who wanted you to know how to make a Horcrux, and that this is how you found out about his Horcruxes. When I first told you about You-Know-Who’s Horcruxes, and told you they’re most likely jewelry, you looked down at my ring. The same thing happened when I told you how we destroyed the first two Horcruxes."