Wondrous Item, Rare, 4,400 gp
(Requires Attunement)
This gem has 3 charges. As an action, you can speak the gem’s command word and expend 1 charge. For the next 10 minutes, you have truesight to a range of 120 feet when you peer through the gem.
The gem regains 1d3 expended charges daily at dawn.