LODESTONE

A lodestone, also called a focus, its a piece of equipment that grants
a multiplier to the damage of a particular spell. When identify is cast
on one of these objects, it will reveal the spell that the item is a
focus for, and a relative description of the multiplier amount. The
description tiers, in order from highest to lowest, are:

Superior
Excellent
Good
Fair
Weak
Abysmal

It is possible for two items to have the same tier in the description,
but be of different strengths. In other words, Focus A and Focus B
might both show 'Excellent', but Focus B is still slightly stronger
than Focus A.

Note that this focus should not be confused with the FOCUS donation
equipment, which has a completely different function.