Elder Scrolls IV: Oblivion - GQ Change Soul Gem Size

GQ Change Soul Gem Size
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This mod for for Elder Scrolls IV: Oblivion requires the Oblivion Script Extender.

This mod for Elder Scrolls IV: Oblivion lets the player change the size of soul gems. Any souls contained are lost. Non-vanilla Oblivion soulgems can be upgraded or downgraded, but only into vanilla soulgems.
The basic ratio is 3:1. Not having high enough Alteration and Mysticism skills can increase the number of soulgems required to upgrade, or decrease the number of soulgems returned from a downgrade.

To upgrade a soul gem, throw down one of the type to be upgraded. While looking at it, equip a Ceramic Bowl (UpperBowlCeramic01, Form ID 2507a).
To downgrade, do the same but equip a Stone Mug (LowerClassMug01, Form ID 104cb).

The upgrade script does not count pre-filled gems with empty or player-filled ones. Use another mod to empty them first (e.g., GQ Magicka From Soul Gems).

KNOWN ISSUE: Gem stack counts in inventory do not always update immediately. To force an immediate update drop the entire stack and pick it up again.