Soul Gem ( Oblivion ) A Soul Gem is an item in . It is a magic stone capable of storing the " soul " of a creature . The gems are used to recharge magical weapons , or to create new enchantments . Locations . Soul Gems are available for purchase from most alchemical and magical merchants . They can also be looted from mages and necromancers . Value . Empty Soul gems , whether looted or bought , have a value based on the grade of the gem , which does not change if filled later . Merchant gems sold or found filled with a soul have a value based on the level of the soul , regardless of the grade of gem . Charging . There are a few ways to charge Soul Gems : Types . Soul gems come in various sizes . The bigger the gem , the greater the " soul " that can be stored in it : Azura ' s Star . Azura ' s Star is a reusable Soul Gem , obtained by completing Azura ' s quest at the Shrine of Azura . Black Soul Gem . Black Soul Gems hold humanoid souls ( Imperial , Argonian , Khajiit , etc . , as well as Daedric Kyn ) . All others , including Azura ' s Star , hold only the souls of creatures . All humanoid souls have a " grand " value , making the value of a humanoid soul equal to that of a Gloom Wraith . Since the power level of an enchantment from Grand and Black Soul Gems are identical , this equality of soul value makes the creation of Black Soul Gems a basically unnecessary process once you start encountering more creatures possessing a Grand soul . Creation . Black Soul Gems are created by placing a Grand Soul Gem in one of four necromancer altar s in Cyrodiil , then casting Soul Trap on the altar at the appropriate time . They can also occasionally be found on necromancers . Colossal Black Soul Gem . The Colossal Black Soul Gem is a special black soul gem with a larger capacity created by Falcar that was meant to hold the soul of Hannibal Traven . Unique soul gems . On the first floor of the Leyawiin Mages Guild resides a display case , containing uniquely sized and colored soul gems . The cabinet requires a key to open , but the key is nowhere to be found . Console commands can be used to unlock the case , but the gems cannot be added to the inventory or moved . Trapping a Soul . To use Soul Trap without having to cast the actual spell , it is possible to enchant a weapon with the " Soul Trap " spell for a one - second duration . This second is sufficient in case the enchanted weapon is used to give the killing blow . If the weapon has a damaging enchantment of more than 1 second , the soul trap effect has to last longer . For example , a sword dealing five seconds of fire damage would need a soul trap effect of at least 6 seconds . An alternative method that can be used by spellcasters would be to create a spell that deals damage and to supplement this spell with a soul trap spell . Again , the soul trap duration would need to exceed that of the other spell by at least one second . Lastly , it is also possible to soul trap creatures that the player has conjured . Actively killing the creature is required however ; simply letting the spell expire is not sufficient to trap the soul . Another easy way to fill soul gems is to get a Black Soul Gem and duplicate it with a duplicate items glitch . If you have the Staff of Worms ( dropped by Mannimarco during the Confront the King quest ) , go to one of the Bandit or Marauder camps around Cyrodiil . Kill all of the Bandits / Marauders except for one . Soul Trap this one , and kill it . Then , use the Staff of Worms to reanimate a dead bandit . Wait a few seconds , then Soul Trap it and kill it . It will count as a humanoid soul . Continue this process for as long as you like . Locations in the Wizard ' s Tower plug - in . An easy place to pick up soul gems are the vault guards in Frostcrag Spire if the Wizard ' s Tower plug - in is installed . All guards have a soul value of Greater and respawn in three in - game days .