It's stamped 18K. I don't know what the material is or if it's really 18K, as I'm a novice. If you're concerned, please go elsewhere. See it with your own eyes and buy it in a store. I don't need any troublesome comments. Just don't buy it. The chain length is approximately 50cm. *Please check the photos. I am a novice and cannot authenticate it, so please only purchase if you are satisfied with the photos! To prevent switching, please refrain from cancellations! I ask that those who purchase immediately and provide proper receipt evaluations do so. I will understand that you have agreed to these terms at the time of purchase. Thank you for viewing.