On the large map look at the little spikes - there are 3 at the bottom right of the map in hive zora. You need the top one of these three.

This entrance way looks like a letter U on the mini map.
Enter (heading south) and follow tunnel ignoring any round rooms you see on the way (2).
Go straight through the X room to the spiral room beyond.
Crystal is in the middle.
geode druid stormscale