Can obsidian be used for gel fire pit rocks?

Yes, obsidian can be used for gel fire pit rocks, but it is not a common choice. Obsidian is a volcanic glass that can withstand high temperatures, making it suitable for use in fire features. However, it may not provide the same aesthetic or functional qualities as more traditional materials like lava rock or ceramic stones. Additionally, care should be taken to ensure that the obsidian pieces are properly sized and shaped for safe use in a fire pit.