This color collection groups entries recorded under the black color label across materials such as Obsidian, Agate, Tourmaline, and Jasper. Their documented forms include tumbled stones, towers, spheres, and chips, so the page supports color-first browsing without replacing the separate material categories.
Use Obsidian, Agate, Tourmaline, and Jasper as material checkpoints within this color group. Then review tumbled stones, towers, spheres, and chips as distinct formats, preserving the catalogue's separation between color, material, and shape.