Sterling Silver Celtic Trinity Knot Triquetra Spin Meditation Motion Ring(Sizes 4,5,6,7,8,9,10,11,12,13,14,15) Center of the Ring Spins 9mm Wide With Triquetra Celtic Knot Symbols Weight Varies from 8.5 to 11 grams (based upon size) Nickel Free Sterling Silver Marked .925 (for Sterling Silver)