Stone Type: Manufactured materials

Ceramic Retouched ceramic

Human-produced materials are sometimes sufficiently siliceous to flake into tools.  Examples include glass and highly-fired stoneware ceramics.  Smelted metals such as copper and bronze—and, more recently, iron—were used to flake stone, and glassy metallurgical slags are often suitable for flaking.  Most modern hobbyist flintknappers prefer to use copper tools for both percussion and pressure flaking. 

Ceramic

Clay fired at a high temperature—such as stoneware or porcelain ceramics—behaves in a similar way to chert.  Ceramic fragments from recycled vessels or insulators served as substitute for stone once these high-fired materials became available.  It was retouched by percussion flaking into hand-held tools, or served as blanks for pressure flaking into points and knives.

Retouched ceramic

Retouched Ceramic

Glass

Glass is created by fusing molten sand with soda and lime and cooling it rapidly. It is amorphous in structure, contains about 70-75% silica, and is ideal for flaking.  Obsidian is a naturally-occuring glass erupted by volcanoes, and industrial smelting furnaces can produce glass as a byproduct.  First Nations people sometimes used glass as a substitute for stone in the recent past.

Bottle base core 1

Glass Core

Bottle base core 3

Glass Core

Bottle base core 2

Glass Core

Bottle glass flake 2, Australia

Glass Flake

Bottle glass flake 1, Australia

Glass Flake

Kimberley point, milk glass

Kimberley Point