Septaria SLAB NOTEBlocks and slabs vary in appearance and dimension.All pictures are a rough guide. OTHERS Precioustone Black Obsidian Picture Jasper Crazy Lace Agate Purple Graphic Brown Obsidian Haematoid Quartz RetrĂ² Petrified Wood Dragon Stone Sodalite Blue Brown Petrified Wood Natural Agate Red Jasper “Classic”