ARK: Survival Evolved Wiki

Ferroceric flint that holds an edge better than regular stone.
— In-game Description

Flint is a natural resource that can be gathered from stones using a pick or, the hatchet, or a creature. The most effective way being the Metal Pick or via Ankylosaurus. The Industrial Grinder can also grind 2 Stone into 1 Flint.

Flint is used for some weapon and tool creation and construction.