Onyx. Chalcedony in parallel layers of different shades of color. It is used for making cameos, the figure being cut in one layer with the next layer as a background. It is stained black and used to make mourning jewelry.

---

“Even though I walk through the darkest valley, I will fear no evil, for you are with me; your rod and your staff, they comfort me.”
– Psalm 23:4