Working Women Rock Silvertone Medium Pi - Teach Inspire Guide Affirmation Necklace Silver Tone Medium Pi - Teach Inspire Guide Affirmation Necklace. Silver Tone Medium Pi is approx. 0.59 x 0.47 x 0.08 (HxWxD) including loop. The irrational number Pi is a mathematical constant, the ratio of a circle's circumference to its diameter, approximately 3.14. It has been represented by the Greek letter since the mid-18th century. Silver tone 2mm Rolo Chain Affirmation Ring Necklace is approx. 24 Inches. Affirmation Ring is approx. 0.86 x 0.86 x 0.05 (HxWxD). Lobster Claw Clasp. This inspirational piece of jewelry is very meaningful. Its circular shape is symbolic for endless belief in the message that is imprinted around the ring. These are motivational or sentimental messages to the wearer. Makes a wonderful teacher gift! You can return this item for any reason and get a full refund: no shipping charges. The item must be returned in new and unused condition. Go to Your Orders to start the return Print the return shipping label Ship it!