These gray clasts breaking up as they flow through the black melt give this piece a great range of contrast and brightness.  The front is polished sterling.  This is from a slice of NWA 13119 and is set in a hypoallergenic, tarnish resistant sterling silver with a pure silver bezel.  A 20 inch heavy weight sterling silver rounded box chain, 1.8mm, is included. It is tarnish resistant silver, not plated, and does not contain any nickel so it is hypoallergenic. I can make this chain in any length.