Channeling Runes

You hold a glass bead between your forefinger and thumb and trace a rune in the air that stays suspended before you for the spell's duration. On any of your spellcasts within this spell's duration, you can expend the rune in place of performing any verbal somatic or material components, not including material components with a gold cost.
The number of runes increases when you reach higher levels, becoming 2 runes at 5th level 3 runes at 11th level and 4 runes at 17th level When you expend one rune the rest remain suspended in the air before you until you expend them at a later time within the spell's duration.