American Fire Glass CG-ONYX-M-10-J Onyx Medium Fire Glass 10 lb Jar. Onyx is no ordinary material, but the stuff of legends. Tales of this mysterious and beautiful stone date back to Greek mythology. It was prized and used extensively by many ancient civilizations including the Romans and Egyptians for making jewelry and carvings. Now, we have succeeded in capturing some of the beauty of onyx in our fire glass so that your customers can bring its exotic features to their homes. Our onyx medium fire pit glass may be described as dark, elegant, mysterious and exotic all at once! Made from recycled glass, these gleaming black fire glass pieces are guaranteed to impress all onlookers with their opaque luster. Ideal for any outdoor environment, this magnificent glass is especially suited to backgrounds of light shade which will contrast with its stunning black. This medium variety is chunkier as compared with our onyx small fire pit glass, which allows for better air circulation and also delivers a bigger and more impressive flame. When your customers' fire pit is lighted, all eyes will stare in wonder at the amazing display as the dark black fire glass shines and reflects the bright yellow flames dancing above it.