Very nice larger blue forest petrified wood slab with swirling green from center. Nice ring details. Nice blacks and greens. That is not dust (mostly) in the matrix, but an interesting spattering of whitish material. Very interesting piece with excellent polish. Measures about 5 1/2 inches wide, 4 1/4 inches tall and is just about 1/2 inch thick. Weighs 1 lb 3 ounces.