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.
“Therefore, I urge you, brothers, in view of God's mercy, to offer your bodies as living sacrifices, holy and pleasing to God – this is your spiritual act of worship.”
– Romans 12:1