I hand form these out of 18 gauge (1.02mm) 100% recycled solid 14k gold, 100% recycled gold fill, 100% recycled sterling silver, pure niobium or pure titanium and smooth the tips. Oval hoops sit closer to the nostril. The inner diameter is measured at the longest point of the hoop, top to bottom and they are ordered in the same size as a well-fitted round hoop. Kristina is wearing an 18g 7mm sterling silver. Shots 3-5: 18g 7mm id sterling silver Shots 6-8: 18g 7mm id hammered sterling siler Shot