Invisible Aegis

The caster begins by rolling the marble around the target object, tracing complex occult patterns. The caster then touches the iron key to the target object four times. The caster repeats the process of rolling the marble and touching the key to the target object three more times, though with each iteration, the marble becomes harder and harder to move, as if it were being pushed through thickening cement. Upon successful completion of the ritual, the marble disappears, and a small, invisible sphere of force surrounds the target object. Any creature holding the iron key used as the focus can pick up and move the target object. Any other creature attempting to touch the target object meets a solid, immovable surface similar to a wall of force. The protective sphere dissipates after 1 month, but it ends immediately if a creature holding the iron key taps it to the object four times in quick succession.