What are false signals?
False signals are sometimes called “phantom” signals. They occur any time your detector responds to metal when there is actually no metal there. False signals are most often caused by naturally occurring iron oxides, such as magnetite and hematite. Magnetite is the primary constituent of the “black sand” that commonly occurs in placer gold deposits. Most Fisher models have automatic ground balancing to accommodate without a false signal but the most severe deposits of mineralization. If your detector has a manual ground-balance adjustment, you can usually tune out false signals. Sometimes you may need to ground tune frequently if the mineralization of the soil changes abruptly as you move from one place to another. If ground mineralization is excessive, turning down your detector’s sensitivity may be the only solution.
