Spiderweb Obsidian Slabs
Obsidian is volcanic glass. It often has flow lines that create interesting
effects. Obsidian has a reputation for being difficult to polish.
Usually the reason for difficult polishing is that coarse grits can
create a fairly deep fracture zone that doesn't come out when the
stone is cut at finer grits. Another problem is obsidian doesn't polish
well if it gets too hot. So, if you don't use super coarse grinding
wheels and if you keep your polishing wheel slow and wet, good results
will easily be obtained.
Spiderweb Obsidian Cab