Orim of the Shadow:
This box seems to be impregnable. On each side is a space where a jewel should be, and the spaces all seem to form a kind of lock. The box will open only when all 6 jewels are placed in their spaces, in the right order. Opening the box will be something of a challenge.
This book has pictures of the 6 jewels. You must find them. In the meantime, I will try to find out which order they must be placed in.
There is a jewelry auction at the Luxury Gallery of the Town of Giran. You should go and check there first.