Double flow or banded obsidian from Montgomery Pass, NV is a unique obsidian with translucent gray/black and thin opaque bands of black obsidian running parallel which gives the appearance of looking through a Venician blind. (Stock 543) Laminate thin slabs together for fantastic patterns. Sizes are from 1/2-5 pounds each. Price listed is for one pound. See a sample slab of double flow or banded obsidian.