You’ll use them in the room of requirement
Hogwarts Legacy has a lot of currencies to juggle, but Moonstones are thankfully fairly straightforward. They’re used to build new aesthetic and mechanical upgrades for your own personal Room of Requirement, which makes a return in Hogwarts Legacy to aid students in need. Here’s how to gather up more Moonstones.
What are moonstones used for?
Moonstones are used to customize your own Room of Requirement instance. Think of it like an apartment in an MMO or open world RPG.
They’re the core currency you’ll need to conjure up anything in your room, from paintings to mirrors, to micro-shops.
Trash things in your personal Room of Requirement to get a Moonstone refund
On the way into the Room of Requirement during the questline, you’ll be introduced to the simplest way to gather up Moonstone: use Evanesco (which you’ll get for the quest) to “vanish” items with a nice Moonstone refund.
When you enter your own personal space near the end of the quest, you’ll be able to use this mechanic yourself. Try aiming at some of the pictures on the wall and using Evanesco on them. You’ll get some Moonstone back, which you can then use for a bigger non-aesthetic upgrade (like a desk to brew potions).
If you’re extremely practical and don’t care about how your room looks, trash everything outside of gameplay-related furniture, and use the Moonstone to build practical objects with the conjure spell.
Building Material Refiners are also an option for passive Moonstone income. You can buy the recipe for Material Refiners via Tomes and Scrolls in Hogsmeade for a whopping 1,500 gold.
You can also find Moonstones in the open world
Eventually you will run out of your finite economy of Moonstones, so you may want to take to the open world to look for them, and increase your cache. Typically, they can be found near mountainsides, and require a basic cast to break apart. For reference, I found some Moonstone in the ravine at the location in the gallery above.
Just make sure you have flight unlocked before you start looking for them to make things way easier.