James writes - Here is some Obsidian That I found myself in Lassen/Davis
Creek California. There are rainbow, sheen and lace varieties.
I polished these babies in my 15 lb Thumblers model B. They went for 14 days in 60-90 grit, (recharged every 7 days) 7 days in 120-220 grit, 7 days
in 500 grit and 14 days in Tin Oxide polish with lots of plastic pellets during steps 2, 3, and 4. I'll admit, I should have added a 5th, 1000 grit step but I was feeling lazy.
I'd like to thank donwrob for the great advice on the final polish for Obsidian!