Onyx

Considered one of the most rare and beautiful materials in nature, due to its translucency, ability to be back-lit, and sleek, modern look. Onyx is typically used in decorative applications, as it is the most vulnerable to chemical and mechanical incidents, and may scratch, stain, and etch more easily. 

Onyx is created in caves from stalactite and stalagmite drippings, which form this striking stone. Because of its unique formaetion, Onyx generally comes in swirling, colorful patterns.