This page of the Baldurs Gate 3 game guide describes how to open the gold chest that is located near the Owlbear Nest. There is a small puzzle associated with the opening of the box, and below you will find the solution.
Owlbear Nest is located in the Forest, west of Druid Grove. One of the entrances to the great cavern is shown in the pictures above.
On the way to the nest, you may encounter a group of cultists, and if you handle the conversation well, they may also set off towards the nest with the intention of murdering the owlbear. Fortunately, in order to open the chest from the described puzzle, it is not required to fight the aforementioned monster.
Once inside the cavern, explore the first area before you reach the actual owlbear's nest. There is a Gilded Chest (shown in the screenshot), which is next to the statue of Selune.
Don't try to open that chest right away, because you're going to receive a lot of damage. The chest is protected by magic. This means that you cannot use a tool kit or a set to defuse traps to open it.
Go to the back of the statue. There, you can pass the perception and religion tests, as well as find the Selunite Prayer Sheet. If you're having trouble finding this item, hold down the ALT key and then click on its name.
Return to the area with the chest. Open the inventory and select a newly acquired object from it. The idea is to read the prayer.
If you have done all the steps correctly, you should hear a comment about the chest being opened.
The chest contains:
- Silver Necklace
- Idol of Selune
Additional note - If Shdowheart travels with the team, she may object to taking things from the chest. You can convince her to change her mind by completing one of the skillchecks (e.g. intuition, persuasion, or intimidation). Alternatively, you can return to the chest with a different party.