This guide will let you know where to get Diamonds and Lithium in Subnautica.
You will need to look for shale outcrops since they can drop gold, LIthium, and diamonds. The two main places you can find are the Jellyshroom caves and the sea treaders’ path. You have to start from the coral tube that sticks up out of the water and head about two notches to the right of the southeast on the compass until you reach a large hole/cave entrance in the ground.
All you are going to really need if you’re going in the caves is a sea moth with an Mk1-MK2 depth module, a high or ultra capacity 02 tanks, and a sea glide or flashlight. The only threat you will encounter in the jelly shroom caves is the crab snake which you can either avoid or ward off using perimeter defense.
The next place is the sea treader’s path, which you can reach by again starting from the coral tube that sticks up out of the water and heading about two notches so the right of the southwest on the compass until you reach the sea treader’s path. All you are going to really need again is a sea moth with an MK1-MK2 depth module, a high or ultra capacity 02 tanks, and a sea glide or flashlight. You also may want to bring a knife in case you run into a warper.
The only threat you will really encounter on the sea treader’s path are warpers which warp you even if you are in a vehicle. You can try to avoid them but if they do warp you, you can either run from them using a sea glide or attack them using your knife until it warps away.
