Soul Gem (Oblivion)

A Soul Gem is an object capable of storing the soul of a dead being. Soul gems come in various sizes, ranging from petty to  . The greater the gem, the greater a soul can be stored in it. These trapped souls can then later be used to recharge magical weapons or to create new enchantments.

To capture a soul, you must have an empty soul gem in your inventory. Cast the Soul Trap spell on the target, and slay it before the duration runs out. If done correctly, the soul will be trapped in the first appropriate soul gem available in your inventory. If no soul gems large enough for the class of soul is available, an error message will displayed and the spell will fail. Be warned that in the opposite event (there is no small enough stone available) a larger stone will be used instead, effectively wasting the larger gem, as soul gems are not reusable.