Arcane Crystal

These small shards of magical energy can restore lost spellpower. When you crush a spell gem in your hand, you recover expended spell slots. Roll 1d4+1; the recovered slots can have a combined level equal to the total, though none of the slots can be of 6th level or higher.

For example, if you rolled a total of 3, you could recover three 1st-level slots, one 3rd-level slot, or a combination of a 1st- and 2nd-level slot.

Special: For the purposes of the magic item rarities presented in Xanathar's Guide to Everything and Tasha's Cauldron of Everything, Arcane Crystals are considered "Uncommon+"