This is a ring with a natural apatite stone. It's one size fits all and adjustable. Stone setting size: Approximately 11mm x 13mm ● Due to the camera, the color appears slightly darker. Images 1 and 2 are closer to the actual color than image 4. The metal part is a silver-colored alloy. Apatite is said to primarily have effects as a power stone, such as mental stability, improved communication skills, easing anxiety, balancing the mind, and facilitating self-expression and smooth interpersonal relationships.