Wand of Treasure Finding

This wand is adorned with gold and silver inlay and topped with a faceted crystal. The wand has 7 charges. While holding it, you can use an action and expend 1 charge to speak its command word. For 1 minute, you know the direction and approximate distance of the nearest mass or collection of precious metals or minerals within 60 feet. You can concentrate on a specific metal or mineral, such as silver, gold, or diamonds. If the specific metal or mineral is within 60 feet, you are able to discern all locations in which it is found and the approximate amount in each location. The wand's magic can penetrate most barriers, but it is blocked by 3 feet of wood or dirt, 1 foot of stone, 1 inch of common metal, or a thin sheet of lead. The effect ends if you stop holding the wand. The wand regains 1d6 + 1 expended charges daily at dawn. If you expend the wand's last charge, roll a d20. On a 1, the wand turns to lead and becomes nonmagical.