Already present in Borderlands 2, even in the third chapter of the series you can collect pieces of Eridium. In this guide, we will give you a hand in finding the sources of Eridium and how to destroy the chests containing the precious material.
There are mainly two ways to get Eridium, it is much easier than you think, but once you find a box and find that it is virtually unbreakable, most may be discouraged. Let's see, then, how to open the chests of Eridium and make it low.
Borderlands 3 | Eridium: what is it and where is it located
In Borderlands 3 , Eridium is used for various purposes: you can buy cosmetic items from Sanctuary III shop, or use an Eridium slot machine to try your luck and find weapons and very interesting items. If you are lucky enough, you can drop a legendary weapon from one of these slots. Eridium can also be used as ammunition for a particular gun, so it's good to have a lot of it with you at all times.
Where is this equipment? Mainly there are two sources: the chests and crystals of eridium that can be destroyed to collect the fragments. The chests are easily recognizable: they are chests with purple crystals all over the surface. You will soon discover that these chests are unbreakable, just like the stacks of eridium. So how can you get eridium? By finding an object that we will describe in the next paragraph.
Note: Strangely enough, Eridium-infected corpses can be easily destroyed, so you'll be able to collect part of this precious resource right from the bodies, without the need for any object. The amount of material collected from this secondary source, however, is laughable.
How to open the chests and destroy the crystals of Eridium
It will take a while before you can start collecting this precious resource because Eridium boxes and heaps of Eridium can only be destroyed once you discover a special artifact, a sort of sonar that with its sound can destroy crystals. Finding the device is simple: just go on with the main story. Everything happens naturally, so you can't lose it.
To be more specific (don't read if you don't want spoilers), the Eridium device is in the middle of the game, once you reach the Great Vault on Promethea. In the underground chamber of the Forgotten Basilica, you will encounter a furious monster after unlocking the vault's entrance.
As a reward, you will receive a special sonar-like device that will allow you to destroy Eridium clusters and open the speakers. To open a chest, you only have to destroy the Eridium around it, so you'll be free to open it.
The device is a permanent item and you don't need to equip it or anything like that. It's not part of your inventory, so you'll be able to destroy Eridium fully automatically once you get the device.
Eridium is very, very useful. The advice is to go back to the areas you have already visited and destroy the crystals, since for half of the game, all the chests you will encounter will not be openable due to the lack of the device that allows you to do so. Once done, open the chests in the new areas that you will unlock. Soon you will have an excellent escort.