Elemental Essence Shard

Wondrous item, rare (requires attunement by a sorcerer)

Description not available (not OGL).
But here is a summary:

Fly, resistance to one damage type, 2d10 fire, or 2d6 cold in 10-ft radius after using Metamagic option on a spell.
Tasha´s Cauldron of Everything

Fragment d'essence élémentaire
  1. DnD 5e Magic Items › Elemental Essence Shard
Elemental Essence Shard