Once you enter the dungeon, keep going to your left. As you reach the farthest northeastern part of the mine, you should enter the small room with the shard inside. When you eventually find it, you’ll notice where this skyshard got its name from.
Find and enter Sandblown Mine solo dungeon.
Entrance to Sandblown Mine shown on the map screenshot above.
“Blown down a mine shaft”.
Exact location of the collectible in the mine.
Sand Kingdom Moons - Super Mario Odyssey Power Moons