Vortigern's Persistent Enchantment

Vortigern's Persistent Enchantment  readies an item to be enchanted with a spell of level five or lower.
The casting time for Vortigern's Persistent Enchantment is 30 minutes for a cantrip, or one hour per spell slot of the spell the item is to be enchanted with.

During the casting of the spell, the silk cord is used to bind the gem to the item; the cord will be consumed in the casting of the spell, while the gem will be fused to the item at its point of placement.

After Vortigern's Persistent Enchantment is successfully cast, the enchanting spell must be cast into the gem-infused item within the next 24 hours, or the preparation is lost and the item may not be safely enchanted.  For every hour that passes after the first before the additional enchantment is begun, there is a -1 on the DC success roll upon completion.  If the DC roll is a failure, then the difference between the DC and the roll is added to the roll on the "Enchanting Failures" table.

A static enchantment on an item (such as a Magic Weapon spell) is permanent.  An effect spell, such as Lightning Bolt, counts as one usage (charge) of the spell, with the charge being restored once every 24 hour period (usually at dawn) as specified by the caster during the spell.  If the goal was to enchant the item with two charges of Lightning Bolt, then Vortigern's Persistent Enchantment would need to be cast over six hours, using a 6th level spell slot, and the Lightning Bolt spell would need to be cast into the gem twice following the successful preparation.