Thank you jimmy......https://www.youtube.com/watch?v=th-oXosPN2M
I lasted about 10 seconds and then got distracted by the other videos running down along the right side of the YouTube page and ended up watching one about casting obsidian. Turns out you can do it but you have to grind it into a powder and then heat it to over 2000 degrees. :)
Now that's a hot video!