Fire opal has a Mohs hardness of 5.5 to 6, which is soft enough that it can be scratched by many objects that it might encounter during everyday wear. Fire opal also has a low tenacity, which means that it can easily be chipped or broken.

Fire opal is best used in jewelry such as earrings, pins, and pendants that usually are not subjected to rough wear. If a fire opal is set into a ring, a setting especially designed to protect the stone from abrasion and impact is recommended.