'An Elemental Qi Essence fragment.' Even without touching it, Re'Kha was able to know about it. After all, in her grey sand world, it was a sharp blank space. But, her Wind Qi perception was unable to determine which element the Element Qi Essence conformed towards.
So, Re'Kha touched the part, feeling something soft and smooth on her finger. She was unable to touch the Elemental Qi Essence, preventing her from knowing what it was. After all, every Elemental Qi Essence would allow her to perceive something upon touch.
A Water Qi Essence would make her hear the sounds of flowing water and feel like the air turned humid all of a sudden. A Fire Qi Essence would make the air feel hot, a Lightning Qi Essence would make her feel numb, and a Metal Qi Essence would make her feel heavy while a ringing sound resounded in her ears. So, it was easy to determine an Elemental Qi Essence's attribute just by touching.