The Chisel is one of the Tools that can be obtained from the Gathering skill. To obtain this tool, there is a prerequisite gathering level of 50. After meeting this requirement, gathering in the Desert Mines will yield you a 1/20,000 chance of obtaining the chisel per bag.
Uses
Obtaining Geodes
The chisel can be used to obtain Geodes and other mining resources in trace amounts. Geodes can be cracked open to obtain these mining resources, along with minerals that are used primarily to craft Rings of different tiers, which are used in other skills such as Combat.
Upgrading the chisel with Gems will allow you to obtain higher-level geodes.