If you must have a special size please specify. Dacite is opaque to very slightly translucent, medium gray to black in color and is slightly grainier than glassy obsidian. It looks more like stone than obsidian. A consistent material available in good sizes. Consistent but somewhat brittle, obsidian produces a chipped stone blade of scalpel sharpness.
Colors are grey, black, mahogany, mixed lots only.
May contain some dacite. Much finer-grained than a quartzite, this material appears to be a porous limestone that has been almost completely replaced with opal and chalcedony. It works quite well without heating, produces replicas that look amazingly old, and is available in large sizes at low cost. This was an aboriginally preferred material for large Benton Points in south central Mississippi. Not as easy to work as heated novaculite, obsidian or dacite, but a very good value.