Obsidian - 10 pounds* due to the crystals lining

due to the crystals lining the inner cavity

are hollow

Hardness: The hardness of geodes can vary depending on the minerals inside

Color: Petrified wood can display a wide range of colors depending on the minerals present during the fossilization process

giving it a somewhat shiny appearance

Obsidian - 10 pounds* due to the crystals liningNatural Obsidian from Mexico Mostly large pieces 1 5 pieces per 10 pounds *Requires 20lbs of shipping space Obsidian is a naturally occurring volcanic glass that typically forms when lava cools rapidly without sufficient time for crystal growth. Color: Obsidian comes in various colors, including black, brown, gray, and green. The most common is black obsidian, which is often referred to simply as "obsidian." Hardness: Obsidian has a hardness of