CAVEMASTER DEMO PARTY
a shiny rock used for making tools
Obsidian is natural volcanic glass. Like chert, it can be knapped into points, blades, and so on. It is generally more fragile than chert, but can also be much sharper.
Items made of obsidian can be very shiny and even transparent. Sometimes the material comes in a striking color. This can make it especially pretty and appealing.
As a surgical tool, obsidian is valuable. Meso-American people found that wounds it made healed more quickly. Obsidian blades are even sharper than modern steel blades.
Sometimes obsidian was used as material for sculpture. Worked patiently with abrasives, it takes on a gleaming luster.