In jewelry designs, as in fashion, all colors look crisper when used with black. Thus Black Onyx is perfect as a background for thin layer of Opal, for knife handle, or even set in gold or silver jewelry. Our Black Onyx slabs come in a variety of thickness to suit almost any purpose. This material has been dyed, as almost all Black Onyx is, but the black color does penetrate all the way through each slab.