SRD:Rod of Metal and Mineral Detection
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Metal and Mineral Detection: This rod pulses in the wielder’s hand and points to the largest mass of metal within 30 feet. However, the wielder can concentrate on a specific metal or mineral. If the specific mineral is within 30 feet, the rod points to any places it is located, and the rod wielder knows the approximate quantity as well. If more than one deposit of the specified metal or mineral is within range, the rod points to the largest cache first. Each operation requires a full-round action.